This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetic and genetic disorders, Subject name: Pediatrics
If the first child is heterozygous and the wife is homozygous for an autosomal-recessive gene, what will be the outcome? 
Select and explain. 
A. 75% children affected, B. No child affected, but all are carriers, C. 50% children affected, rest are carriers, D. 25% children affected, rest are carriers
C: 50% children affected, rest are carriers
Answer: C: 50% children affected, rest are carriers 
Explanation: If the husband is heterozygous and the wife is homozygous for an autosomal recessive gene, 50% of the children will be affected; the rest will be carriers. This is pseudo-dominant inheritance, which refers to the observation of apparent dominant (parent to child) transmission of a known autosomal-recessive disorder, or it can also mean the inheritance of a recessive trait mimics a dominant pattern. This occurs when a homozygous affected individual has a paner who is a heterozygous carrier, and their children have 1 in 2 chance to get affected (50%) Ref: Nelson textbook of pediatrics 21st edition Pgno: 645