Freckles are dominant to plain skin and the freckle gene is on an autosome. Becker muscular dystrophy is inherited as X-linked recessive trait. The parents are healthy and both have freckles. They have an affected son with plain skin. Draw up the family pedigree. Find the genotypes. a) What is the chance that they will have a daughter who has the disease and who has freckles? Inheritance of Freckles and Becker Muscular Dystrophy: Analyzing a Family Pedigree

Becker Muscular Dystrophy, Inheritance of Freckles: Analysis of the Family Pedigree 

The following is an image of a Becker muscular dystrophy-afflicted family. The parents, who are both healthy, have freckles. However, the son has normal skin. It is essential to understand how freckles are inherited and the reasons behind them in order to analyze the pedigree. BMD and freckles can be caused by a dominant genetic trait on the autosome. (Kremer 2018; Aitken et. al. 2020). Before we can calculate the likelihood of a couple having a girl with BMD, or freckles, let’s first identify the genetics of the family members. The parents have been found to be heterozygous for freckles genes, while the son has the same gene. The father’s genotype for the BMD gene is unknown, but the mother must be either heterozygous or homozygous recessive (Aitken et al., 2020). A couple’s chance of having a child with BMD or freckles will depend on the genetic makeup of their mother. A 25% chance that the daughter will have both BMD genes is for a mother who is heterozygous. The chances of having both the BMD and homozygous recessive genes-positive mothers are 0% (Kremer 2018, 2018). Cont…