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Trong thoi doi phat trien, benh to IcS can tar nen pha bien trong xa hc)i,.dac. Wet la a tre Khi benh mai ducc phat hien, nguai to cho rang nguyen nhan gay benh chit yeu do yeu to mai truing song, str thieu quan tam tir cha me va nh4ng nguai co trach nhiem day do. Tir da se clan den firth twig tre kern phat trien toin dien ve mat neon nga, giao tiep va gag hoat clang xa ,hai. Thai gian gin day, viec nghien ciru can benh nay da cO met buoc tien mai khi cac nha khoa hoc da bat dau tim ra nhitng gen c6 kha nang gay benh do xay ra hien Wong dot bien gen. Tir day, mat nhan dinh duoc dua ra de là benh tkr kjr co the c6 kha nang di truyen to bo,me sang con cal. Trong so nhung gen c6 kha nang gay benh, gen SHANK3 yeu to dung vao ir6 quan trong nhat, ben canh nhCrng gen khac nhu NLGN3, NLGN4X,... FISH (floumescent in situ hybridization) va aCGH (array comparative genomic hybridization) la hai phuong phap chinh duce sir dung de phat hien nhung sai khac tren gen hay tren nhiem sac the, ben canh d6 de xic nhan lai nhung thay dal do, phuong phip MLPA (multiplex ligation probe amplification) se duce clung den. Ben canh viec tim ra nhung rot loan ye di tntyen, nhimg lieu phap chera tri cling dirge ap dung de gin) cho benh nhan cc, the mph dan han trong viec giao tiep, trong nhung hoot dang xa hai va nhan biet nhung sit vat, hien tuong xung quanh. Tuy nhien, cho den nay, mat cau hei van chtra co lai giii la sit twang quan gifra kieu hinh, kieu gen cita benh va sv twang tic gifra nhimg yeu to di truyen va hoar girth m8i tnreng. Trong tuang lai gin, neu nhung thic mac nay c6 lei giii dap chinh xac thi se la mat tien ba len trong viec ngan chart va dieu tri can benh nay.
Tap chi Cling nghe Sinh hoc 12(1): 1-9, 2014 BAI TONG QUAN YEU TO DI TRUYEN GAY BENH Tir KY . O THE EM: HIEN TRANG VA CAC PHIXONG PHAP CHAN DOAN Le Bic Vi0, Nang Van Hal, Nguyen Huy Mang Vien Nghien ctitt he gen, Vien Han lam Khoa hoc vet Cong nghe Viet Nam Ngay nhan bai:18.8.2013 Ngay nhan clang: 05.3.2014 TOM TAT Trong thoi doi phat trien, benh to IcS/ r a ng can tar nen pha bien trong xa hc)i,.dac . Wet la a tre Khi benh mai ducc phat hien, nguai to cho rang nguyen nhan gay benh chit yeu do yeu to mai truing song, str thieu quan tam tir cha me va nh4ng nguai co trach nhiem day do. Tir da se clan den firth twig tre kern phat trien toin dien ve mat neon nga, giao tiep va gag hoat clang xa , hai. Thai gian gin day, viec nghien ciru can benh nay da cO met buoc tien mai khi cac nha khoa hoc da bat dau tim ra nhitng gen c6 kha nang gay benh do xay ra hien Wong dot bien gen. Tir day, mat nhan dinh duoc dua ra de là benh tkr kjr co the c6 kha nang di truyen to bo , me sang con cal. Trong so nhung gen c6 kha nang gay benh, gen SHANK3 yeu to dung vao ir6 quan trong nhat, ben canh nhCrng gen khac n h u NLGN3, NLGN4X, FISH (floumescent in situ hybridization) va aCGH (array comparative genomic hybridization) la hai phuong phap chinh duce sir dung de phat hien nhung sai khac tren gen hay tren nhiem sac the, ben canh d6 de xic nhan lai nhung thay dal do, phuong phip MLPA (multiplex ligation probe amplification) se duce clung den. Ben canh viec tim ra nhung rot loan ye di tntyen, nhimg lieu phap chera tri cling dirge ap dung de gin!) cho benh nhan cc!, the mph dan han trong viec giao tiep, trong nhung hoot dang xa hai va nhan biet nhung sit vat, hien tuong xung quanh. Tuy nhien, cho den nay, mat cau hei van chtra co lai giii la sit twang quan gifra kieu hinh, kieu gen cita benh va sv twang tic gifra nhimg yeu to di truyen va hoar' girth m8i tnreng. Trong tuang lai gin, neu nhung thic mac nay c6 lei giii dap chinh xac thi se la mat tien ba len trong viec ngan chart va dieu tri can benh nay. Tit khoa: aCGH, benh ttr 4, di truyJn, &Of ban gen, FISH, gen SHANK3, MLPA GIOI THIEU Dinh nghia ve bdnh tv kY' len dAu tiep duqc nha khoa hoc nguai My Leo Kanner dua ra vao nam 1943. Khi d6, ttr ky ducfc cho là benh gay ra nhimg • rot loan phat trien he than kinh a nguai benh bang cach lam thay dOi su lien ket va to chin giaa to bao thAn kinh va cac khop than kinh. Benh thuOng bee phat ngay tv khi benh nhan con nh6, nett kitting duric phat hien semi va co nhang lieu phap dieu tri thich hop, benh se ngay cang nang han va benh nhan thuong c6 xu htrang tranh xa moi hoat &Ong xung quanh mirth, khong muon tiep xtic vii nguai Ichfic va c6 nhung hanh ding bit thu6ng. Ve ca ban, su thieu nhung hoat deng va giao tiep xa hai, nen nga la diu hien not bat trong moi berth nhan tv Icy. Dar Ming là tieu chuin yang de chin doin lam sang doi vii nhung ngirtri bi nghi nga mac tv ki tai cac Benh vien chuyen khoa Nhi. Nguyen nhan ma tin tnrac den nay van duoc cho la nye tiep va chit yeti nit& la sv thieu quan tam, chain s6c dimg each tir cha mg nal rieng va cac bac nuoi day n6i chung. Chinh dieu nay da khiAn cho tit khong ductc , phattrien met each toan dien the , chat, tinh than va dac biet là he than kink. Lau dan, nhung roi loan ve than kinh tang dan len, tao nen 06 roi loan tu ky (autism spectrum disorders - ASD) yeti niang bieu hien rat ro rang ve tinh each, hanh Ong va suy nghT (Autism Association, 1994). Thai gian gin day, vii nhung nen ba nhay 'KA trong y hoc, sinh hoc phan tir, sinh hoc to bao, chin doin, mat nguyen nhan mai gay bath tkr kjf da , ittroc tim ra. DO nhOng sv roi loan chuyen h6a, mat can bang sinh hOa trong ca the do det bien tren cac gen chirc nang gay ra. Nhiffig gen nay m4 Ma cho clic protein lien quan trVc tiep den he thong than kinh va nhting khap than kinh trong ca the. Do do, (tat bien xay ra ten nh!ng gen nay se tnjc tiep gay ra nhang h6i chung roi loan thAn kinh c6 bieuhien lam sang giOng nhu benh tv kY. Mang det bien clAu 1 0.012 0.01 0.009 0.008 .00625 ar 0.006 0.004 0.004 0.001 0.002 O. 00 11 0 ■ 0.01 0.0065 0.005 , 0 .0 0.1 0.008 0.0012 0.0015 sCs 4 -\ 6' 0 1 " 1 o, a " 4 9 ' ce \I P S b Cl= 4 4 V s • e -V" ""k s • (sP ,N1 tien da duqc tim thy tren cac gen inh hu6ng den kh6p thin kinh nhu gen SHANK3 (SH3 and multiple ankyrin repeat domains 3) (Gauthier et al., 2009; Moessner et al., 2007) NLGN3 (Neuroligin 3) va NLGN4X (Neuroginin 4, X-linked) (Jamain et al., 2003; Laumonnier et al., 2004). Trong do, nhung d6t bien tren gen SHANK3 duqc cho la yeu to chit yeu hcm tat ca giy ra ph8 rOi loan tq kY hay con goi la h6i chimg Phelan — McDermid (Durand et al., 2007). Ben canh do, sq ph& trien cUa ceng nghe giai ma town b6 he gen ngu6i ding viec tim ra nhung bien the s6 lumg ban sao chep (copy number variations — CNVs) da gifip tim ra duqc nhung bien the di truyen . giy inh hung 16n den benh kY cling nhu khang dinh met cich chic chin tam quan trong cua chirc 'tang khop thin kinh d6i vai benh tr k9 (Autism Genome Project, 2007). Cac nghien ceu sau de da tim ra nhung CNV ten phirc he gen NLGN-NRXN-SHANK Ara hai gen !chop thin kinh Mac nhu SynGAP va DLGAP (Berkel et al., 2010; Marshall et al., 2008; Pinto et al., 2010). Tuy nhien, cho den nay, tucmg quan giea kieu hinh vi kieu gen dm benh nhin van chua duqc lim sang to. Trong bii bio nay, chUng toi de cap den cac phucmg phi!) sinh hoc phin tir de Oat hien (let Wen gen giy benh de tit d6 c6 the chin dofin benh nhanh hon (tong th6i gifip cac bac &I dua ra nhung 16i khuyen heti ich cling nhu phip s dieu tri dung din. 1XNH VA CAC YEU TO DI TRUYEN ANH HONG Le Bic Viet et al. TInh hinh b?nh tv ky hi4n nay Tien the gi6i, nhung nghien ciru yr trtrac nam 1985 ve tS l I:41th tv lc* va nhung dieu kien lien quan cho ket qui 5 tru&ng hqp troll 1000 tre em dual 18 tuoi. Te nhung nam 1980, so ca mac benh duqc chin doin thanh c8ng tang len vOi t6c d6 nhanh ch6ng. Met Olin la do nhung tien 136 cua y hoc chin doin va chinh phli cling da diu to nhieu ham vac) Unit vqc y to dOC biet là nhung benh lien quan den thin kinh (Blumberg, 2013). Trung tam Kiem sat vi Phong ch6ng benh (CDC) 6 My da dua ra t9 le tre mac nhung rOi loan tkr ky tren town ciu hien nay dat mem 12 ca trong 1000 tre em (American Autism Centers, 2011). Tai My, ts, le tlr k9 tinh tlr nhung nam 1980 den nay di tang gip den 10 lin, uorc tinh 1/110 tre em (1%) duqc chin doin mic , benh. Dieu nay a ding duqc giii thich bai loi s ong ngAy cang thqc dung tai My. Ben canh my, Anh cling IA met mac co t9 le tq kjr dat muc cao (xip xi 1%) (Autism Society, 2006). Ngoai Anh vi My co ty le mac tlr k9 cao, benh nay cling co inh huerng tren khap cac qu6c gia tren the gi6i. Tuy nhien, rat kh6 de xac dinh chinh xic tY le nay. Posserud ding c6ng skr (Autism Society, 2010; Autism Speaks, 2008) da th6ng ke ts, le tv ks , cua met s6 qu6c gia tren The gi6i trii deu tren khap cac Chau lqc (tre Chau Phi) dqa tren sq chin elan tkr kY 6 cac tre em song tren dit nuac de (Autism Speaks, 2008; Posserud et al., 2010) (Hlnh 1). Do ty 1(9 co the xiy ra dOng th&i va a bi nham Ian vai nhieu benh khic ye mat thin kinh nen de tinh toan chinh xic tY le mac benh la met viec tucrng doi kh6 khan. Hinh 1. Tlnh hInh bOnh tit kjr tai mOt s6 quOc gia hen thO giai. Tap chi Cling nghe Sinh hoc 12(1): 1-9, 2014 Tai Viet Nam, cho den nay van chua c6 met dieu tra, thong ke chinh thirc ve benh to kSr. Neu chieu theo ti le cua Anh quec, Viet Nam hien c6 83 trien dan thi c6 160.000 ngu&i to VS/. Ben canh do, theo so lieu cita Be Thucmg binh vi Xa hei c6 khoang tir 5- 7% tre em tan tit 6 dO tuoi clued 15, trong de tre em to 1(9 va bai nao chiem khoang tren 40%. Ngoai ra, trong so nhung tre ducc chin doin xic djnh li to IcS, trong giai doan ttl. 2008 — 2011, chi Ichoing 12% so tre duqc phit hien cic diu hieu cua berth truck 2 tuoi; 19,74% so tre duqc phit hien li do co giao chit khong phai b8 mg hay 8ng bi; 56,58% tre duqc phit hien benh nha diu hieu chim not (tre da han 2 thing tuoi). Ben canh do, theo nghien cuu me hinh tan tit & tre em cua Khoa Phuc hoi chirc nang Benh vien Nhi Trung uang, giai doan 2000-2007, so lucmg tre duqc chin doin va dieu trj to lc Se ngay cing s deng; tre to k9 den khim nam 2007 tang gap 50 lan so vii nam 2000; s6 tre to IcS , den dieu tri nam 2007 tang gip 33 lan so yeti nam 2000. Xu the mac to lcSr tang nhanh tir 122% den 268% trong giai doan 2004-2007 so yin nam 2000. Theo cic thong ke tir Berth vien Nhi deng I, TP HO Chi Minh, nam 2000, Benh vien chi dieu trj cho 2 , tre bj to k9, thi sau 4 nam con se nay da li 170 tre, den nam 2008 con so nay tang gip gin 2 lan tirc la 324 tre. Bieu hien lam sang binh ter 1[5 , 6 benh to 1c9, rei loan phit trien he thin kinh chinh la Neu hien lam sing tieu bieu nhit. N6 bao gem nhieu trieu chimg khic nhau & ngu&i benh, tip trung lai ph6 rOi loan to icy (autism spectrum disorders - ASD). Trong do, n6i , nhat chinh li so kern phit trien toan din tre mac benh, dac biet IA kha nang sir dung ngen nprei kern, chim biet n6i; ngai hoac khong muen giao tiep van ngtr&i khic; tir do din den cic hoat deng xa hei bj kim ham met cich tei da. DOi vii nhung hinh dOng sinh hoat hang ngiy, tre thuting co xu htreing lam nhung viec lap di lap lai theo bin nang ma khong chju ngei yen met ch6 hay con goi la hien tuong tang deng (Lam and Aman, 2007). Hien Wong nay lai bao gem nhieu bieu hien khic nhu ngu&i benh hay c6 hinh dOng quay co tay, quay diu hay c6 nhung hinh Ong c6 tinh bat buec vi du nhu xep de chaff, bitp be, , 0 to thinh met hang ngang hoac doc. Nguy hiem nhat chinh la benh nhan l ai hay to lam minh bj thuong nhu: lay tay choc len mat, dm len da, to danh vao tay, vao dau. Met nghien cuv vao nam 2007 da bao cao ve hien wow nay vii ti le 30% benh nhan c6 dau hieu rei loan to kk (Dominick et aL, 2007). M6t van da nava la Ire mac benh thuong c6 khi 'tang di lai chim han nhieu so vii tre Ichic, thuong phii mit 2-3 num tuoi mai di lai binh thuong duqc. Ngoai ra, kha tang lien lac bang mat cita tre thoc so kheng tot vi benh nhi thuong c6 thii de he( hung vii moi thir xung quanh. Nhiing yiu to gay benh b cap de di truyen hue Benh to 1c9 , c6 nen tang di truyen rat manh, n6 Bong Op len den khoang 90% kha 'tang benh to Ic9 phit trien & tre em va thong thu&ng duqc chi ra bei cic gen ttrcmg ung (Hallmayer et al., 2011). Mac di' viy, so di truyen benh rat phirc tap vi khong re rang (Abrahams and Geschwind, 2008; Buxbaum, 2009). Nhiing nghien ciru ye nhung cap song sinh da cho thay so di truyen benh to 1c9 c6 xic suit la 0,7 vi dei vii phe roi loan to kS , len an 0,9. Dac biet doi yen nhang cap song sinh la con gii thi kith nang di truyen to IcS , gap tai 25 lin so vii ngu&i binh thuong (Geschwind, 2009). Tuy nhien, cho den nay, nhifmg det bien c6 nguy ca gay to ky vi 016 r6i loan tkr ky van chua duqc xic djnh het. Nhung diet Wen nay c6 the là det bien don gen (det bien chi xiy ra tren met gen) hoac IA nhang bien dei bat thu&ng tren nhiem sic the (NST). Nhung det bien NST nay gay ra ntrOng hei chirng benh khic nhau lien quan den phis) rei loan to kjf (Abrahams and Geschwind, 2008). Nguyen nhan gay benh bit nguen tir nhi - mg hien the so Itrong sao chep (copy number variations) tren gen qui djnh, nhung bien the nay c6 the li mat doan, lap doan, them doan, dio doan tren gen hoac NST (Cook and Scherer, 2008). Berth to Ic9 c6 tinh di truyen nhung Ichong chic chin c6 tinh ke filth. Dieu de the hien & ch6: con cai mac benh tuy nhien be mg van c6 the hoan toan binh thu&ng, khoe manh duqc goi la ngu&i mang mam benh (Beaudet, 2007). Thai gian gin day, met s6 gen vi NST c6 nguy ca gay ra to Ic9 vi phe rOi loan to k , S, da duqc cic nhi khoa hoc tim ra. Nhung det bien vi bien doi bat thu&ng tren nhiing gen nay gay ra nhting hei chimg khicnhau, tang vii mOi loai phe red loan to Ic9 vi mei hei chirng duqc dat ten theo nha khoa hoc da phit hien ra n6: hei chirng Asperger vii gen NLGN3 va NLGN4X (Jamain et al., 2003; Laumonnier., 2004); hei cluing Phelan- McDermid vii gen SHANK3 (Durand et al., 2007; Gauthier et al., 2009; Moessner et al., 2007), hei chirng nay con co ten khac la hei chirng x6a NST 22q13. CA 3 gen nay deu c6 diem chung la anh htrang troc tiep den so phit trien cua trung tam than kinh. 3 Le Bic Viet et al. Gen SHANK3 ma h6a cho met loai protein lien quan truc tiep den cac khap than kinh giau proline. Gen nay nam tren NST canh dai 22q13. Ve mat chat nang, gen SHANK3 la mot thanh vien trop lien hQ gen SHANK. Cac protein SHANK deu bao gom nhieu vOng (domain), la nhiing protein xoan hinh , khan, duqc sinh ra ki sau phin bao. Chung ket tivc tiep diem thy cam he thong can truyen than kinh, cac kenh ion va nhang protein mang khac den actin cytoskeleton va G-protein. Protein SHANK kheng nhthig ce chirc nang kiem soat to chac mit dO khap than kil!' ma con c6 }chi nang tao phirc he receptor khap thin kinh, phin tir tin hieu va protein lien quan den to bao xuang c6 trong tity cOt song (Boeckers et al., 2002; Naisbitt et aL, 1999). Trong do, protein SHANK3 c6 the tao lien ket yeti to bao protein thin kinh (Meyer et al., 2004). Do viy, trong so 3 gen chirc nang anh huang den henh tu kSr ke tren, gen SHANK3 duqc coi la nhin to ce anh huang manh me nhit de giy ra pho rAi loan tv kS , a ngu&i benh. Gen SHANK3 la met gen c6 kich thuac rat Ion len den khoang 60 kb, bao gOm 23 exon. Trong de exon 23 co kich thuac dai nhat va eking vai Ire quan trong trong viec *ay ra hOi chang x6a NST 22q13 - met hOi chimg rat dac trung cua H) p roi loan to kjt. Gen NLGN3 nam tren NST X ma h6a cho protein Neuroligin-3, la met thanh vien trong lien hQ protein neuroligin trong nhOrn cac protein be mat to bio thin kinh. Neuroligin tham gia vao ciu tao va dinh hinh nen trung tam he thong thin kinh. Nhiing bien the (mit, them, dao doan) tren gen nay di duqc xac dinh, tuy nhien toan bO trinh tu doan gen cho den nay yin chua duqc xac dinh chinh xac. Gen NLGN4X ma h6a cho protein Neuroligin-4, X-link. Protein nay din* thuOc hQ neuroligin nen cimg ca vai fro *An giOng nhu neuroligin-3. Gen NLGN4X ding nam tren NST X, c6 kich thuac Ichoang 5,5 Mb. Khac vai gen NLGN3, hi4n nay, mai chi c6 2 bien the duqc xac dinh tren gen NLGN4X. WO Men teen gen SHANK3 va hOi chfing x6a NST 22q13 Nhiing hien the tren gen SHANK3 hau hit la mat met doan DNA Ian, do dO hien Urging nay con g9i la hpi chang xoa NST 22ti13. HOi , chirng nay mang gin nhu dAy m9i diu hieu rOi loan dm benh to kS, nhu da neu a tren, do da gen nay duqc coi nhu nhin to chu ch8t trong viec giy benh tg Icy. Trong do, dOt bien x6a toan be exon cuoi hinh thanh hei chung benh rat dien hinh cua hqi chirng Phelan-McDermid, ten g9i khac la hOi chung x6a NST 22q13. Hien tuqn* mit doan tren NST 22q13 bit nguon tir nhaing mat doan nucleotide, skr hoan vi gen hoac su thay doi cau trfic anh huang den NST canh dai 22. Kich thuac doan gen bi x6a tren NST 22q13 thuang dao dOng trong Ichoing 100 kb den 9 Mb chia lam 3 loai da la: xoa met doan nho, xoa doan rat nh6 va xoa doan Ian. Nhimg nghien ciru truac day da chi ra x6a doan nh6 giy ra pho roi loan dac trung cua benh tu kSt, x6a doan lon co xu , huang giy ra nhang kieu hinh nghiem trQng nhit va x6a doan rat nh6 mang nhising diem ca ban cua hOi chang x6a NST 22q13 da dirge bao tir tnrac (Moessner et al., 2007). Bonaglia cung tong skr da liet ke duqc nhang mit doan tren NST 22q13 tren 42 benh nhan nghien ciru (Bonaglia et al., 2011) (Bang 1). Bang 1. Danh sach nhCrng mat doan m6iduvc tim thay tren NST 22q13. Banh Gi6i Plurcrng phap Nhiem sac tha Loai dat Won Kich thveoc Ngulin gOc nhan tinh doan bi xoa di truyen 1 Nam FISH Del(22)(q13.3) X6a nucleotide tai exon cuoi 0.9 Mb Cha me 2 NO , Phan tich NST Del(22)(q13.31) X6a nucleotide tai exon cu6i 5.38 Mb Cha me 3 ND FISH Del(22)(q13.32) X6a nucleotide tai exon cuOi 2.5 Mb Me 4 Nam FISH Del(22)(q 13.32) X6a nucleotide tai exon cuOi 1.64 Mb Chua xac dinh 5 NCr Phan tich NST Del(22)(q13.31) X6a nucleotide tai exon cuOi 6.5 Mb Cha me 6 Nam FISH Del(22)(q 13.32) X6a nucleotide tai exon cu6i 2.65Mb Me 7 Nam FISH Del(22)(q13.31) X6a nucleotide tai exon cuOi 3.5 Mb Me 8 Nam Phan tich NST Del(22)(q13.32) X6a nucleotide tai exon cu6i 8.1 Mb Cha me 9 NCr FISH Del(22)(q13.31) X6a nucleotide tai exon cuOi 0.8 Mb Cha me 10 NCr Phan tich NST Del(22)(q13.2) X6a nucleotide tai exon cuoi 8.1 Mb China xac dinh 11 NCr aCGH Del(22)(q13.31) X6a nucleotide tai exon cuOi 4.98Mb Cha me 4 Tap chi Gong ngh" Sinh hoc 12( 1 ): 1-9, 2014 12 NO , aCGH Del(22)(q13.3) X6a nucleotide tai exon cuoi 1.08 Mb China xac dinh 13 NO , Phan tich NST Del(22)(q13.31) X6a nucleotide tai exon cuoi 5.8 Mb China xac dinh 14 Nam Phan tich NST Del(22)(q13.2) X6a nucleotide tai exon cuoi 7.6 Mb Cha me B§nh Gibs Pturceng phap Nhiem sac the Loai d6t bran Kich thuhfrc Ngu6n g6c nhan tinh doan bj x6a di truyen 15 NO' FISH Del(22)(q13.31) X6a nucleotide tai exon cuoi 4.7 Mb Chu , a xac dinh 16 Nam FISH Del(22)(q13) X6a nucleotide tai exon cuoi 3.7 Mb Chive xac dinh 17 NO' Phan tich NST Del(22)q(13.2q1 X6a nucleotide tai exon cuoi 7.2 Mb Cha me 3.3) 18 NCr FISH Del(22)(q13.31) X6a nucleotide tai exon cu6i 4.7 Mb Mg 19 NO , FISH Del(22)(q13.32) X6a nucleotide tai exon cuoi 1.9 Mb Mg 20 Nam aCGH Del(22)(q13.31) X6a nucleotide tai exon cu6i 3.4 Mb Cha me 22 NO , aCGH Del(22)(q13.32) X6a nucleotide tai exon cu6i 1.8 Mb Cha me 23 NCr aCGH Del(22)(q13.31) X6a nucleotide tai exon cuoi 3.4 Mb Cha mg 24 Nam aCGH, MLPA Del(22)(q13.33) X6a nucleotide tai exon cuoi -122 Kb Cha me 25 NO' aCGH Del(22)(q13.33) X6a nucleotide tai exon cuoi -122 Kb Cha me 26 Nam FISH Del(22)(q13.31) X6a nucleotide tai exon cuoi 4.4 Mb Cha me 27 Nam FISH Del(22)(q13.31) X6a nucleotide tai exon cuoi -4 Mb Cha me 28 NCr Phan tich NST Del(22)(q13.2) X6a nucleotide tai exon cuoi 9.0 Mb Cha me 29 Nam aCGH Del(22)(q13) X6a nucleotide tai exon cuoi 122 Kb Cha me 30 NCr Phan tich NST Del(22)(q13.2q1 X6a nucleotide tai exon cuoi 7.4 Mb Me 3.3) 31 NO' Phan tich NST Del(22)(q13.31q X6a nucleotide tai exon cuoi 5.8 Mb Cha mg 13.3) 32 NO' aCGH Del(22)(q 13.3q 1 X6a nucleotide & giO , a NST -74 Kb Cha me 3.3) 33 NO , aCGH Del(22)(q13.3q1 3.3) X6a nucleotide b giCya NST -44 Kb Cha mg 34 Nam aCGH Del(22)(q13.3q1 X6a nucleotide & giDa NST -18 Kb Chiya xac dinh 3.3) 35 NCr aCGH Del(22)(q13.3q1 X6a nucleotide 6 , giCra NST -27 Kb Chu , a xac dinh 3.3) 36 Nam aCGH Del(22)(q13.3q1 X6a nucleotide a gift NST -39 Kb Chiya xac dinh 3.3) 37 NCr Phan tich NST Del(22)(q13.32) Ring 22 2.16 Mb Cha me 38 NO' Phan tich NST Del(22)(q13.33) Ring 22 1.2 Mb Chu , a xac dinh 39 Nam Phan tich NST Del(22)(q13.31) Ring 22 5.2 Mb Me 40 NCr Ph5n tich NST Del(22)(q13.33) Ring 22 0.45 Mb Me 41 Nam Phan tich NST Del(22)(q13.31) Ring 22 3.2 Mb Cha me 42 Nam Phan tich NST Del(22)(q13.32) Ring 22 2.04 Mb Cha me CAC PHUONG PHAP CHAN DOAN 0 CAP DO PHAN TU, TE BAO Nhu di nal u tren, nhang d6t bi6n hay nhang bien the so luting sao chep tren nhirng gen chirc nang lien quan den he thong thin kinh anh huang den benh to kY hau het la nhang mat doan, lip doan hoic dao doan. Do d6, de Oat hien &roc nhirrig bat thuang nay, doi hoi phai can Ai) dung ca flitting phuong phap sinh hoc phan to ciing nhu sinh hoc to bao. Nhang phtrang phap hien dai va dang duac clang ph6 bien nhat hien nay la array comparative genomic hybridization (aCGH), fluorescence in situ hybridization (FISH). Ben canh do, multiplex ligation probe amplification (MLPA) la in6t phuang Olaf) ding rat hiTru ich &roc dung , nham xac nhan lai nhang mat doan hoc d6t bien diem di tim 5 Le Bic Viet et al. they bang cac phucmg phap traac do. Ngoai 3 phucmg phap hay clang den a tren, phuong phap giai trinh iv the he mai di buac dau duqc img dung nha lcha nang doc duqc trinh to met doan DNA caa ne. Phtrang phip array comparative genomic hybridization (aCGH) aCGH la met phuong phap duqc sir dung de xac djnh nhen bien the trong phien ban sao chep caa genome nhu them hoac mat NST hay met phan NST. Ve nguyen li tien hash phuong phap aCGH, man dua vao thi nghiem lute phai gem it !that 2 Mau, do la man 'dem tra (test) va mau doi chimg (control). Nheng mau nay la DNA tong so di duqc tach chiet tir trtrac do va hoin toan dO dieu Ici'e'n ve de tinh sach. Mat khac, phuong phap doi hoi nhang matt do dac hieu cho nheng (loan DNA nghi ng6 bj x6a hoac chen them nucleotide. Mau de nay la nheng doan oligonucleotide co kich thuac tir 20-85 nucleotide. Cuei cling, yeu to Ichong kern phan quan tong khac caa aCGH la nheng tin hieu lai (hybridization signals). Tin hien lai nay la nheng mau huSmh quang duqc nhuem vao man lam tra, trong !chi mau doi chimg duqc nhuem vai met loai mau dac trung khac. Trong phucmg phap aCGH, tin hieu lai nay chinh la yeo to quan tong de nhan biet c6 hay Ichong nheng su bat thuang trong gen/doan DNA ma minh dang nghien cau. Dua vao phucmg phi') nay, 10 dot bien va 14 (let bien mit doan tren NST 22q13 Ian lugt di phat hien thay tren cac nghien ciru cita Bonaglia va Soorya cling cac cong su (Bonaglia et al., 2011; Soorya et al., 2013). Phtroug phi') gild trinh ttr the he mai Giai trinh to the he mai (illumina dye sequencing) la met ki thuat ducc sir dung a xac djnh 4 loai cac baza nits tren doan DNA dua ten nhimg mau quknh dac hieu cho mOi loai bazo nits. Su tien be cua phuong phap nay the hien 6 the n6 c6 the xac djnh duqc trinh to a ca nheng 'yang khe doe va nheng trinh to lap lai. Trong nghien ciru oh Chaste ding cling cong stir, phuong phap giai trinh ttr mai tren may illumina di buac dau duqc img dung de phat hien 5 bien the tren met se gen va NST c6 lcha nang gay phe rei loan to kk (Chaster and Leboyer, 2012). Phuong phdp MLPA icy thu4t MLPA (multiplex ligation probe amplification) la met ki thuat sir dung nheng man del (probe) dac hien duqc khuich dai nh6 phan img PCR nham sang loc nhimg (let bien thuong gap tren nheng gen chirc nang gay benh di truyen. Be Kit MLPA duqc thucrng mai h6a tir cong ty MRC Holland, Amsterdam, Ha Lan. Vai tro . chinh caa MLPA trong nghien benh ttr Ick la nham kiem tra xac nh4n lai ket (let bien mit 'Joan hoac dot bien diem di duqc tim thay nha phuong phip cac phucrng phap phan tich NST hoac giai trinh AL Cho den nay, di co tong cong 37 mall de duqc sir dung cho NST 22q13 va 4 trong so de dac hien cho gen SHANK3. Plurong phap FISH FISH (lai huknh quang trong to bao) la met ki thuat di truyen hoc to bao duqc cac nha nghien ciru y sinh hoc phat then vao dau nheng nam 1980. Phuang phap nay clung de phat hien va khoanh vimg cac diem mat hoac ellen them nucleotide 6 cac trinh tv DNA trong NST. FISH sir dung nheng mau do huknh quang gan vao nhimg phan mong muen cua NST. DO phat hien nhang yang gin dm mau do huknh quang len NST, kinh hien vi huknh quang can duqc sir dung. FISH thuang duqc sir dung de tim ra nhang diem dac tnmg trong DNA nham dua ra nheng 16i khuyen di truyen, xac djnh loai va thuoc mai. Doi vai phuong phap nay, met mau do can duqc thiet ke. Mau de phai c6 kich thuac du km de lai met cach dac hieu vai DNA dich nhung cling khong duqc qua Ian se rat de gay kim yam qua trinh lai. Mau de duqc gan duOi truc fiep vai huknh quang, can vai DNA dich la Idling the. Thuc te, FISH la phuong phap di truyen hoc to bao ducc biet den nhieu nhat trong viec phat hien nhemg bat thuang tren NST (Durand et al., 2007). TOng cong di c6 28 OA bien mit doan di tim thay trong nhang nghien ciru cua Bonaglia va Soorya ding cong su ve benh to Ick (Bonaglia et al., 2011; Soorya et al., 2013). TIXONG QUAN GICJA KIEU ILINH VA KIEU GEN Met trong nheng yin de quan tong nhtmg chua duqc giai quyet ki cang la viec am hieu nheng mei ttrcmg quan gift bien the di truyen va kieu hinh benh to kk. Gia thuyet dau tien li giai tinh Ichong den nhat ye kieu hinh cua benh trong suet qua trinh phat trien gay ra su cham phat trien co the 6 ngeri benh. MOt gia thuyet khac la nguyen nhan gay benh den tir ca nheng bien the hiem va thuang gap. Mac du cac nghien can co lien quan trtrac day van chua dua ra duqc nheng bang chirng re rang ye nguyen nhan c6 nguOn gec tir nhtmg hien the ha? , gap 6 benh tu . kk, nhung cac phan tich gan day ye nheng bien the di truyen lien quan den phe roi loan to Ick di dua ra gqi k rang ca nheng bien the hiem hay thuang gap deu 6 Tgp chi Cong nghe Sinh hQc 12(1): 1-9, 2014 c6 the gay ra phO rOi loan tv ky do sir lign loan cfra mang ltrai than kinh (Ben-David and Shifman, 2012). Gia thuyet cuOi cling, khong lien quan den hai gia thuyet tru6c do, la nguyen nhan bat nguan tir nhung yeu to mai truing lam thay doi kieu hinh. SU' TUONG TAC GIUA YEU TO DI TRUYEN VA MOI TRUONG (GxE) Nheng sir khong ang nhAt ve met di truyen c6 the duqc ly giai la do flirting nghien ciru lien quan den benh tv ky van con kha it. Tuy nhien, nheng ket qua nay con c6 the duqc lam sang to drra tren khung hinh mau twang tic GxE (D'Amelio et al., 2005). Ben canh nhung nguyen nhan ye di truyen dA &Km neu a tren, nheng tranh cal xung quanh nguyen nhan bat nguon tra moi truing not len nhu benh nhan c6 tiep xtic vai nhung loai kim loai nAng c6 thu8c tna sau, thuoc diet co, benh truyen nhiem do virus hay nhung hoa chat dOC hai thai ra moi tnnang. MAc du Meng ket qua ban du thu (URN la rat dang khich le, nhtrng gia dinh va benh nhan c6 lien quan den benh tv ky van clura duqc ma rOng nghien dm den sir Wang tic GxE. M'et trong nhung van de chinh trong hinang nghien ciru nay do la kha nang de phat hien nhung twang tic GxE thuang it kha thi hon kha nang phat hien nhung anh huong rieng re dr di truyen hay moi truing. Nheng nghien ciru ye twang tic GxE a trong nhung 1:18i cheng kilt loan thin kinh khac nhau dang din bi lang xwingdo thieu di nhung ket qua tich cuc (Duncan and Keller, 2011). Tuy nhien, nhung ket qua nghien ciru nay van can thiet bai chfing glut) chung to hieu hon ve tinh khong lien trong nhirng nghien ciru ttr twac den nay va tir Q6 Qua an nhung gqi him ich ve phuang phip ngin chAn benh tir sarn. CuAi ding, nhung nghien ciru tiep theo ve moi twang quan giea nhung bien the hiem gAp c6 lien quan den pho rOi loan tit ky va nhung yeu to moi twang tren nhung benh nhan mang cfic dOt bien da duqc xic dinh c6 the se rat hen ich. Tuy nhien, de thuc hien duqc dieu do cling khong he a ding do ,s6 ltrqng ngtnai mang mam benh kh6ng nhieu. 'CET LUAN Cho den nay, nhO sir phat trien cita khoa hQc cOng nghe, dAc biet la linh vuc di truyen hQc da dua den nheng quan niem mai ye ca the phan flit va to bao gay ra benh tu Icy. NO khong chi din gian la do nhung yeu to moi truing ben ngoai tic amg, ma con c6 the do ca nhung rOi loan chric nAng gen. Nhieu cau hal mai se not len, bao gem vai tra cita nhung bien the hay gAp va sir tuong quan gift kieu hinh va kieu gen oh benh. Cuoi ding nhung cling khong kern phan quan trong, str am hieu ye su tuang tic gift nh(tng yen to di truyen va hoan canh moi tnnang la rat can thiet doi vai nghien tiro benh li cita hr ky, tuy nhien de di sau vao nghien ciru su Wang tic nay can doi hoi mot Wong mau benh lin va thai gian nghien ctru lau dii. Uri cam an: Cong trinh nghien citu . nay duqc Myr hien bang sy. ho try kink phi dm de tai cap ca sd Vien Nghien ctiu he gen, Vien Han lam Khoa hQc va Cling nghe Viet Nam. 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Posserud M, Lundervold AJ, Lie SA, Gillberg C (2010) The prevalence of autism spectrum disorders: impact of diagnostic instrument and non-response bias. Soc Psychiatry Psychiatr Epidemiol 45: 319-327. National Autism Society (2006) ASD prevalence, (London, England: National Autistic Society). Soorya L, Kolevzon A, Zweifach J, Lim T, Dobry Y, Schwartz L, Frank Y, Wang AT, Cai G, Parkhomenko E (2013) Prospective investigation of autism and genotype- phenotype correlations in 22q13 deletion syndrome and SHANK3 deficiency. Mol Autism 4: 18 8 Tap chi Cong nglie Sinh h9c 12(1): 1-9, 2014 GENETIC FACTORS CAUSING AUTISM IN CHILDREN: STATUS AND DIAGNOSIS METHODS Le Bac Viet, Nong Van Hai, Nguyen Huy Hoang* Institute of Genome Research, Vietnam Academy of Science and Technology SUMMARY In the modem life, autism is becoming more and more popular in society, especially children. Originally, it was believed that the major cause of this disease is due to environmental factors such as lacking care of parents or teaching responsible people. Therefore, children patients are delayed in entire development of languages, communication and social activities. In recent years, studies of autism have been obtained a great breakthrough when scientists found out genes getting involved in this disease due to mutagenesis. Thus, a consideration was brought out that autism may be well a heritable disease from parents. Among related genes, the SHANK3 gene is the main contribution factor, beside the NLGN3 gene, NLGN4X gene Array comparative genomic hybridization (aCGH) and floumescence in situ hybridization (FISH) are two main methods applied for autism-related genes/chromosomes analysis. Moreover, multiplex ligation probe amplification (MLPA) technique is used to confirm results obtained by two methods above. After diagnosising genetic disorders, some treatment therapies should be implemented in order to encourage autism patients be positive in communicating, social activities and recognizing everything around. However, up to now, two issues which are still debatable and unsolvable, are the relationships between phenotype-genoype and the interactions between genetic factors and environmental backgrounds. In the near future, if these wonders are answered, there will be a significant step in prevention and treatment of autism. Keywords: aCGH, autism, FISH, genetic, MLPA, SHANK3 gene * Author for correspondence: E-mail: nhhoangaigrac.vn 9