ACF Lam, CW Lam, MHY Tang, JWY Chu, STS Lam

Abstract

Hypophosphatasia is a rare inborn error of metabolism. The disease is characterised by skeletal mineralisation and dentition defects. Mutations have been found in the TNSALP gene in various forms of hypophosphatasia. We report the first Chinese case of perinatal lethal form of hypophosphatasia due to previously reported pathogenic compound heterozygous mutation in the TNSALP gene; and successfully applied clinically in prenatal diagnostic testing. The authors emphasised the importance of accurate diagnosis of fetal presentation of skeletal dysplasia for genetic counselling, and discussed its differential diagnoses.