Question

the information in pedigrees that is useful for mapping disease genes is sometimes limited. this pedigree shows segregation of neurofibromatosis, a fully-penetrant, autosomal dominant condition, and a linked snp locus, snp3. why are the genotypes of the children noninformative for determining the degree of linkage between the disease-causing gene nf and snp3?

Answer 1

The genotypes of the children are noninformative for determining the degree of linkage between the disease-causing gene nf and snp3 because they only provide information about the inheritance of the neurofibromatosis gene.

Step-by-step explanation:

In this case, the genotypes of the children are noninformative for determining the degree of linkage between the disease-causing gene nf and snp3 because the genotypes of the children only provide information about the inheritance of the neurofibromatosis gene, not the linked SNP locus snp3. The children could have inherited different combinations of the disease-causing gene nf and snp3, making their genotypes noninformative for determining the linkage between the two.