Which term best describes a genetic disorder resulting from a mutation in a gene located on a non-sex chromosome?

• A. Autosomal
• B. X-linked
• C. Dominant
• D. Recessive

Answer: (A)

The term that best describes a genetic disorder resulting from a mutation in a gene located on a non-sex chromosome is "autosomal." Non-sex chromosomes are referred to as autosomes, and humans have a total of 22 pairs of autosomes, in addition to one pair of sex chromosomes (X and Y).

Disorders arising from mutations in these autosomal genes can be classified further based on their inheritance patterns. For example, if only one copy of the mutated gene is needed for the disorder to manifest, it is considered autosomal dominant. Conversely, if two copies are required for the disorder to appear, it is classified as autosomal recessive. However, in this case, the key point is that the disorder originates from an autosome rather than a sex chromosome, making "autosomal" the most suitable term.

The other terms listed are associated with genetic disorders in different contexts. X-linked refers specifically to genes on the X chromosome, thus not applicable here. Dominant and recessive describe the inheritance patterns but do not specify where the gene is located in terms of sex versus non-sex chromosomes. Therefore, "autosomal" is the defining characteristic for this type of genetic disorder.