What is the inheritance pattern of Hypophosphatasia?

Hypophosphatasia is indeed inherited in an autosomal recessive pattern. This condition is characterized by a deficiency of alkaline phosphatase, which is crucial for the mineralization of bones and teeth. Individuals with hypophosphatasia inherit mutations in the ALPL gene responsible for encoding the tissue-nonspecific alkaline phosphatase enzyme.

In autosomal recessive inheritance, an individual must inherit two copies of the mutated gene (one from each parent) to manifest the condition. Parents who carry one copy of the mutated gene typically do not show symptoms themselves, making it possible for the condition to appear in offspring even if neither parent is affected. This pattern accounts for the variability in severity observed in hypophosphatasia, as individuals may inherit differing combinations of mutant alleles.

Understanding this genetic framework is crucial for counseling patients and families affected by the disorder, as it informs them of recurrence risks in future pregnancies and the implications for family members who may be carriers.