BIOL 4020 Lecture Notes - Lecture 6: Snp Array, Copy-Number Variation, Haplotype
Document Summary
Small region on chr 7q that shows linkage dis-equilibrium between snp markers and ptc teste sensitivity. Region contains a gene that codes for a bitter-taste receptor - member of tas2r family. 3 snp"s give rise to 5 haplotypes around the world: various levels of sensitivity to ptc. About 25% of pop have no sensitivity to ptc. Someone solved the structure of the bitter taste receptor, looked at positioning of the snps: the non-tasting snps result in bulkier a. a. , so that decreases sensitivity to substances. Need a very high-affinity substance to activate it further, so can"t taste a relatively low-affinity substance such as ptc. Snp databases - snpedia etc: humans are not diverse - 95% similar, e coli are much more diverse. Snp creation over history is rare b/c our polymerase has pretty high fidelity - makes a mistake 1 in. All short answer - answer in 1 sentence usually. Small number questions mostly (1 or 2 marks)