Kinky hair disease is a disorder where the affected child has a peculiar white stubby hair, growth retardation, brain degeneration, and dies by age of 2 years. Mrs. A is hesitant about having children because her two sisters had sons who had died from kinky hair disease. Her mother&;s brother also died of the same condition. Which is the possible mode of inheritance in her family?

The mode of inheritance in her family is X-linked recessive The point in our are as follows: Only males have manifested this disease. Females act as carriers; sister&;s sons had the disease X-Linked recessive disorder: Males are affected more commonly and more severely than females Female carriers have a 25% risk for having an affected son, a 25% risk for a carrier daughter, and a 50% chance of having a child that doesnot inherit the mutated X-linked gene. The affected father will have all daughters (100%) to be carriers and unaffected sons because they pass their X chromosome to all of their daughters and their Y chromosome to all of their sons. Ref: Nelson textbook of pediatrics 21st edition Pgno: 645