principles of human genetics ppt

... Chapter 062. Principles of Human Genetics (Part 12) The Genetic Map Given the size and complexity of the human genome, initial efforts aimed at developing ... the identification of disease-causing genes by positional cloning. Recent insights into the structure of the normal human genome show that certain blocks of DNA sequences, often containing numerous ... corresponds to ~1 Mb of DNA (Fig. 62-3). Any polymorphic sequence variation can be useful for mapping purposes. Examples of polymorphic markers include variable number of tandem repeats (VNTRs),...

Ngày tải lên: 07/07/2014, 01:20

... fundamental principles of genetics. The pervasive nature of the role of genetics in medicine makes it imperative for physicians and other health care professionals to become more informed about genetics ... 64). The application of screening and prevention strategies will Chapter 062. Principles of Human Genetics (Part 13) The Human DNA Sequence The complete DNA sequence of each chromosome provides ... primary focus of the HGP was to obtain DNA sequence for the entire human genome as well as model organisms. Although the prospect of determining the complete sequence of the human genome seemed...

Ngày tải lên: 07/07/2014, 01:20

Ngày tải lên: 07/07/2014, 01:20

Ngày tải lên: 07/07/2014, 01:20

Ngày tải lên: 07/07/2014, 01:20

... Medicine > Chapter 62. Principles of Human Genetics Impact of Genetics on Medical Practice Impact of Genetics on Medical Practice: Introduction The beginning of the new millennium was ... distinct forms of Alzheimer's disease, several of which lead to the formation of neurofibrillary tangles (Chap. 365). The identification of defective genes often leads to the detection of cellular ... and the generation of genetic and physical maps by the Human Genome Project (HGP). The consequences of this wealth of knowledge for the practice of medicine are profound. To date, the most...

Ngày tải lên: 07/07/2014, 01:20

... information of eukaryotic genomes Online Mendelian Inheritance in Man http://www.ncbi.nlm.nih.gov/omim/ Online compendium of Mendelian disorders and human genes causing genetic disorders Office ... and Molecular Bases of Inherited Disease (OMMBID) http:/ /genetics. accessmedicine.com Online version of the comprehensive text on The Metabolic and Molecular Bases of Inherited Disease, ... text on The Metabolic and Molecular Bases of Inherited Disease, 8e Chapter 062. Principles of Human Genetics (Part 1) Table 62-1 Selected Databases Relevant for Genomics and Genetic...

Ngày tải lên: 07/07/2014, 01:20

... (or linked genes) with the presence of a disease or genetic trait (see below). Chapter 062. Principles of Human Genetics (Part 4) Figure 62-2 Flow of genetic information. Multiple extracellular ... regulation of gene expression through the interaction of transcription factors with regulatory regions of genes. RNA polymerase transcribes DNA into RNA that is processed to mRNA by excision of intronic ... pairs of sister chromatids (2n →4n). The process of DNA synthesis requires stringent fidelity in order to avoid transmitting errors to subsequent generations of cells. Genetic abnormalities of...

Ngày tải lên: 07/07/2014, 01:20

... Chapter 062. Principles of Human Genetics (Part 5) Figure 62-3 Crossing-over and genetic recombination. During chiasma formation, either of the two sister chromatids on ... sequences upstream (5') of the transcription start site, although there are also examples of control elements within introns or downstream of the coding regions of a gene. The upstream regulatory ... expression profiles, this knowledge may be of diagnostic and therapeutic relevance. The large-scale study of expression profiles, which takes advantage of microarray technologies, is also referred...

Ngày tải lên: 07/07/2014, 01:20

... deletion mutations of the β- globin gene or larger deletions of the globin locus that can also result in Chapter 062. Principles of Human Genetics (Part 6) The number of DNA sequences and ... Figure 62-5 A. Examples of mutations. The coding strand is shown with the encoded amino acid sequence. B. Chromatograms of sequence analyses after amplification of genomic DNA by polymerase ... result in altered expression or splicing of genes. Examples are shown in Fig. 62-5. Figure 62-4 Point mutations causing β-thalassemia as example of allelic heterogeneity. The β-globin gene...

Ngày tải lên: 07/07/2014, 01:20

... Chapter 062. Principles of Human Genetics (Part 7) Transcriptional Activation and Repression Every gene is controlled uniquely, whether in its spatial or temporal pattern of expression ... representative of this group of diseases; mutations in several different islet cell–specific transcription factors cause various forms of MODY (Chap. 338). Table 62-2 Selected Examples of Diseases ... factors account for ~30% of expressed genes. A growing number of identified genetic diseases involve transcription factors (Table 62-2). The MODY (maturity-onset diabetes of the young) disorders...

Ngày tải lên: 07/07/2014, 01:20

... are widely used in genetics and molecular diagnostics, however, it is useful to review briefly some of the fundamental principles of cloning and DNA sequencing. Cloning of Genes Cloning refers ... events. Suppression of gene expression is as important as gene activation in the control of cell differentiation and function. Some mechanisms of repression are the corollary of activation. For ... expression of recombinant proteins, and other recombinant DNA procedures. The cloning of DNA involves the insertion of a DNA fragment into a cloning vector, followed by the propagation of the...

Ngày tải lên: 07/07/2014, 01:20

... Chapter 062. Principles of Human Genetics (Part 9) Nucleic Acid Hybridization Nucleic acid hybridization is a fundamental principle in molecular biology that takes advantage of the fact ... expression pattern of large numbers of mRNA transcripts can be determined by hybridization of RNA samples to cDNA or genomic microarrays. This method has tremendous potential in the era of functional ... and permits comprehensive analyses of gene expression profiles. As one example, microarrays can be used to develop genetic fingerprints of different types of malignancies, providing information...

Ngày tải lên: 07/07/2014, 01:20

... integration of transgene Transgenic Pronuclear injection of transgene Variable copy numbers of transgene Chapter 062. Principles of Human Genetics (Part 10) Transgenic Mice as Models of Genetic ... are relevant to human physiology reflects a surprising conservation of genetic pathways and gene function. Transgenic mouse models have been particularly valuable, because many human and mouse ... be divided into two main approaches: (1) expression of a gene by random insertion into the genome, and (2) deletion or targeted mutagenesis of a gene by homologous recombination with the native...

Ngày tải lên: 07/07/2014, 01:20

... 062. Principles of Human Genetics (Part 14) Transmission of Genetic Disease Origins and Types of Mutations A mutation can be defined as any change in the primary nucleotide sequence of ... an important cause of genetic diversity as well as disease. Mutation rates are difficult to determine in humans because many mutations are silent and because testing is often not adequate to ... at a rate of ~10 –10 /bp per cell division. Germline mutation rates (as opposed to somatic mutations) are relevant in the transmission of genetic disease. Because the population of oocytes...

Ngày tải lên: 07/07/2014, 01:20

... checkpoints. Mutations in the ATM gene give rise to defects in meiosis as Chapter 062. Principles of Human Genetics (Part 15) Unequal Crossing-Over Normally, DNA recombination in germ cells ... function is rescued by the fusion of cells derived from two different forms of xeroderma pigmentosum. Ataxia telangiectasia causes large telangiectatic lesions of the face, cerebellar ataxia, ... effects of ultraviolet irradiation. More than 10 different genes have been shown to cause the different forms of xeroderma pigmentosum. This finding is consistent with the earlier classification of...

Ngày tải lên: 07/07/2014, 01:20

... the ∆F508 deletion of phenylalanine (F) in the CFTR gene are examples of allelic variants of these genes that result in disease. Because each individual has two copies of each chromosome (one ... with a loss of one X chromosomal locus. that certain types of mutations (C →T or G →A) are relatively common, the nature of the genetic code also results in overrepresentation of certain amino ... mutation (see below for discussion of anticipation). Trinucleotide expansion was first recognized as a cause of the fragile X syndrome, one of the most common causes of mental retardation. Other...

Ngày tải lên: 07/07/2014, 01:20

... Chapter 062. Principles of Human Genetics (Part 17) Genotypes describe the specific alleles at a particular locus. For example, there are three common alleles (E2, E3, E4) of the apolipoprotein ... focuses on a panel of mutations that are particularly frequent (often taking the ethnic background of the patient into account), but a negative result does not exclude the presence of a mutation ... the role of specific HLA allelic variants in susceptibility to these autoimmune diseases. The recent characterization of common SNP haplotypes in four populations from different parts of the...

Ngày tải lên: 07/07/2014, 01:20

Ngày tải lên: 07/07/2014, 01:20

Ngày tải lên: 07/07/2014, 01:20