Name Section Question 4 You are studying a common genetic trait. The mutant allele associated with this trait differs from the wild-type allele by a single base-pair(bp) substitution. This substitution eliminates a Nhel restriction site that is present in the wild-type allele. (The mutant allele is not cut by Nhel. )A pedigree of a family exhibiting this trait is shown below normal male normal female affected male fected female You isolate DNA from four individuals in the pedigree. Using PCR techniques, you amplify a 1000 bp portion of their dna which includes the site affected by the mutation. You digest the PCR products with Nhel and analyze the resulting DNA fragments on a gel Individual: 5 6 Nhel Nhel Nhel 1000bp 600bp 400bp a)Based on these data, is this gene located on an autosome or the X-chromosome? Briefly justify your reasoning b)Based on these data, is the mutant phenotype dominant or recessive to wild-type and why? c) If individuals 3 and 4 have a daughter, what is the probability that she will be affected? Justify your reasoning 7012Fall2003Name:___________________________________ Section:_____ 7.012 Fall 2003 7 Question 4 You are studying a common genetic trait. The mutant allele associated with this trait differs from the wild-type allele by a single base-pair (bp) substitution. This substitution eliminates a NheI restriction site that is present in the wild-type allele. (The mutant allele is not cut by NheI.) A pedigree of a family exhibiting this trait is shown below: normal male affected male normal female affected female 1 2 3 4 5 6 7 8 You isolate DNA from four individuals in the pedigree. Using PCR techniques, you amplify a 1000 bp portion of their DNA which includes the site affected by the mutation. You digest the PCR products with NheI and analyze the resulting DNA fragments on a gel: a) Based on these data, is this gene located on an autosome or the X-chromosome? Briefly justify your reasoning. b) Based on these data, is the mutant phenotype dominant or recessive to wild-type and why? c) If individuals 3 and 4 have a daughter, what is the probability that she will be affected? Justify your reasoning. 1000 bp 600 bp 400 bp 5 6 Individual: NheI NheI NheI NheI 6 6 7 6 8 6