In the pedigree below a single gene W determines the trait w

In the pedigree below, a single gene W determines the trait with affected individuals shown as black symbols. Which mode of inheritance is most likely for this pedigree autosomal dominant, autosomal recessive, X-linked recessive or X-linked dominant? State the individuals that support your hypothesis and give your reasoning. Write the genotypes of each of these Individuals on the pedigree: I-3, I-4, 11-2, II-3, II-4, II-5, III-1, III-2

Solution

This a autosomal recessive condition.

Autosomal recessive is a trait, disorder, or disease that can be passed down through families.

An autosomal recessive disorder means two copies of an abnormal gene must be present in order for the disease or trait to develop.

Inheriting a specific disease, condition, or trait depends on the type of chromosome that is affected. The two types are autosomal chromosomes and sex chromosomes. It also depends on whether the trait is dominant or recessive.

A mutation in a gene on one of the first 22 non sex chromosomes can lead to an autosomal disorder.

Genes come in pairs. One gene in each pair comes from the mother, and the other gene comes from the father. Recessive inheritance means both genes in a pair must be abnormal to cause disease. People with only one defective gene in the pair are called carriers. These people are most often not affected with the condition. However, they can pass the abnormal gene to their children.