What type of inheritance pattern does alkaptonuria follow?

What type of inheritance pattern does alkaptonuria follow?

• A. Dominant inheritance
• B. Recessive inheritance
• C. X-linked inheritance
• D. Mitochondrial inheritance

Answer: (B)

Alkaptonuria follows a recessive inheritance pattern. This metabolic disorder results from a deficiency in the enzyme homogentisate 1,2-dioxygenase, which is involved in the degradation of the amino acids phenylalanine and tyrosine. The condition occurs when an individual inherits two copies of the mutated gene, one from each parent, leading to a complete loss of enzyme function. This means that individuals with alkaptonuria must be homozygous for the recessive allele to express the condition, while carriers, who possess one normal allele and one mutated allele, do not show any symptoms of the disease. The recessive inheritance demonstrates that both alleles must be affected for the phenotype to manifest, correlating with the biochemical nature of the condition and its expression in offspring.

Alkaptonuria follows a recessive inheritance pattern. This metabolic disorder results from a deficiency in the enzyme homogentisate 1,2-dioxygenase, which is involved in the degradation of the amino acids phenylalanine and tyrosine. The condition occurs when an individual inherits two copies of the mutated gene, one from each parent, leading to a complete loss of enzyme function. This means that individuals with alkaptonuria must be homozygous for the recessive allele to express the condition, while carriers, who possess one normal allele and one mutated allele, do not show any symptoms of the disease.

The recessive inheritance demonstrates that both alleles must be affected for the phenotype to manifest, correlating with the biochemical nature of the condition and its expression in offspring.