Question

In humans, the DMD gene is required for proper muscle function. Mutations in the DMD gene display X-linked recessive inheritance that leads to muscular dystrophy. The DMD gene has enhancers that are required for gene expression in specific muscles of the body. enh1 is required for expression in the heart; enh2 is required for expression in the arm muscles; enh3 is required for expression in the leg muscles. For an individual with the genotype listed below, what phenotype would you expect

Answer 1

Answer:

Explanation:

As the inheritance is X-linked,recesson so for expression of muscular dystrophy in any given muscle,

$\frac{enh1- enh2+ enh3 - DMD+ }{enh1- enh2+ enh3 + DMD+}$

enh1+ /enh1 + = Shows muscular dystrophy in heart (Homozygous for -)

enh2+/enh2+ = Shows no muscular dystrophy in arms (Homozygous for +)

enh3-/enh3+ = variabl or mosaic for muscular dystrophy in leg muscles (Hetrozygous for enh3)