Question

10 consider the pedigree to the right. (a) i ii iii part a what type of inheritance is displayed? a sex - linked dominate b autosomal dominant c autosomal recessive d sex - linked recessive

Explanation:

• Autosomal recessive inheritance is characterized by the fact that unaffected parents (in generation I, both are unaffected) can have affected offspring (in generation II). In autosomal recessive, two copies of the recessive allele (one from each parent) are needed for an individual to be affected.
• For sex - linked dominant, an affected father would pass the trait to all daughters and for sex - linked recessive, if it was X - linked recessive, a mother who is a carrier (if it was X - linked recessive and the father was normal) would have a 50% chance of sons being affected. But here, the pattern does not match sex - linked dominant or recessive.
• For autosomal dominant, at least one of the parents would be affected if it was autosomal dominant (since only one copy of the dominant allele is needed for the trait to be expressed).

Answer:

C. Autosomal recessive