TAILIEUCHUNG - 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 that the two complementary strands of nucleic acids bind, or hybridize, to one another with very high specificity. The goal of hybridization is to detect specific nucleic acid (DNA or RNA) sequences in a complex background of other sequences. This technique is used for Southern blotting, Northern blotting, and for screening libraries (see above). Further adaptation of hybridization techniques has led to the development of microarray DNA chips. Southern Blot Southern blotting is used to analyze whether genes have been deleted or rearranged | 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 that the two complementary strands of nucleic acids bind or hybridize to one another with very high specificity. The goal of hybridization is to detect specific nucleic acid DNA or RNA sequences in a complex background of other sequences. This technique is used for Southern blotting Northern blotting and for screening libraries see above . Further adaptation of hybridization techniques has led to the development of microarray DNA chips. Southern Blot Southern blotting is used to analyze whether genes have been deleted or rearranged. It is also used to detect restriction fragment length polymorphisms RFLPs . Genomic DNA is digested with restriction endonucleases and separated by gel electrophoresis. Individual fragments can then be transferred to a membrane and detected after hybridization with specific radioactive DNA probes. Because single base-pair mismatches can disrupt the hybridization of short DNA probes oligonucleotides a variation of the Southern blot termed oligonucleotidespecific hybridization OSH uses short oligonucleotides to distinguish normal from mutant genes. Northern Blot Northern blots are used to analyze patterns and levels of gene expression in different tissues. In a Northern blot mRNA is separated on a gel and transferred to a membrane and specific transcripts are detected using radiolabeled DNA as a probe. This technique has been largely supplanted by more sensitive and comprehensive methods such as reverse transcriptase RT -PCR and gene expression arrays on DNA chips see below . Microarray Technology A comprehensive approach to genome-scale studies consists of microarrays or DNA chips. These microarrays consist of thousands of synthetic nucleic acid sequences aligned on thin glass or silicon surfaces. Fluorescently labeled test sample DNA or RNA is hybridized .

• Y học thường thức
• Principles of Human Genetics
• bệnh học và điều trị
• bài giảng bệnh học
• tài liệu y khoa
• Harrisons Internal Medicine
• Biological information
• Lecture Genetics
• Human genetics
• Modern genetic techniques
• Mendels principles
• Mendels principles of heredity