An autosomal recessive disorder is described as:

An autosomal recessive disorder is described as:

• A. A disorder that occurs when two dominant alleles partner up, causing inherited disease.
• B. A disorder that occurs when two recessive alleles partner up, leading to malfunctioning proteins.
• C. A disorder caused by a single mutated allele on the X chromosome.
• D. A disorder that results from mitochondrial DNA mutations.

Answer: (B)

Autosomal recessive disorders require two copies of the mutated allele on an autosome for the disease to manifest. When both copies are mutated, the gene product is typically defective, leading to the disease phenotype. Carriers with one mutated allele are usually asymptomatic because the normal allele provides sufficient function. The other descriptions point to patterns that are autosomal dominant, X-linked, or mitochondrial, which do not fit autosomal recessive inheritance.

Autosomal recessive disorders require two copies of the mutated allele on an autosome for the disease to manifest. When both copies are mutated, the gene product is typically defective, leading to the disease phenotype. Carriers with one mutated allele are usually asymptomatic because the normal allele provides sufficient function. The other descriptions point to patterns that are autosomal dominant, X-linked, or mitochondrial, which do not fit autosomal recessive inheritance.