forensic DNA Monday may 12

Forensic dna monday may 12

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: May 12, 2008 DNA and chromosome structure Wrong interpretation of DNA matches from cold hits-Cops exaggerate signifigence DNA match is not faulted, "odds" are lower because of many chances to find match. DNA uses in society Members of the same species show enormous sequence variation in their genomes. 1 in 1000 bp differ in any two randomly chosen humans. Since haploid genome is 3 109 bp, 3 million differences between any two randomly chosen individuals Most differences are in non-coding, nonregulatory regions. Alleles any variations in the genome at a particular location (locus) Polymorphic two or more alleles at a locus Polymorphism the particular variation DNA marker polymorphic locus useful for mapping studies, disease diagnosis Anonymous locus position on genome with no known function Four classes of DNA polymorphisms Highly polymorphic minisatellites are generated by unequal crossing-over. Repeating units 20-100 bp long Total length of 0.5 20 kb 1 per 100,000 bp, or about 30,000 in whole genome Fig. 11.4 Minisatellite detection and DNA fingerprinting 1985 Alec Jeffreys made two key findings. Each minisatellite locus is highly polymorphic. Most minisatellites o...
View Full Document

Ask a homework question - tutors are online