You are using SNPs (Single nucleotide polymorphisms) to map a leprosy resistance

Question

You are using SNPs (Single nucleotide polymorphisms) to map a leprosy resistance trait (autosomal recessive) in armadillos. You have two strains, San Antonio (resistant) and Austin susceptible) which differ at several hundred SNP markers. Previous work has localized the gene to a particular region of LGVII (which is spanned by markers f1261, k1011, and s0509 in the order shown below). You cross heterozygous F_1 armadillos to each other, and select for resistant F_2s. Most of the offspring are homozygous for the San Antonio alleles at all loci, but some are recombinant (all are homozygous for the resistance gene). The SNP profiles of the three types of recombinants (a, b, c) are shown for each marker. What is the most likely location for the mutant gene? a) upstream of f1261 b) downstream of s0509 c) between f1261 and s0509 d) between k1011 and s0509 e) between 1261 and k1011

Explanation / Answer

Option d. This is because , a sample that is heterozygous at the flanking SNP should have a single heterozygote gene. Here the recombinants are homozygous for resistance geneThe mutation cannot be present at region that are heterozygous. So the 2 SNPs (of recombinants ) mark the left and right boundaries of mutant gene or the gene of interest..It comes between k1011 and s0509.This is the most likely location.

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.