4th March 2024

A 3-year-old boy presents to the genetic clinic after being assessed in the endocrine clinic

A 3-year-old boy presents to the genetic clinic after being assessed in the endocrine clinic as he has been found to have a bowed tibia by his parents in the context of short stature. Blood tests have been taken with normal calcium, PTH and vitamin D levels, raised ALP and moderate hypophosphatemia. He was initially managed with calcitriol but failed. His mother appeared to have been affected by the same condition, and this was managed with calcitriol and phosphate during her childhood. Genetic analysis shows that a mutation within the PHEX gene is responsible for his condition.

What is the method of inheritance for this condition?

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