[Infantile hypophosphatasia due to mutations in the tissue-nonspecific alkaline phosphatase gene].

Objective: To explore the clinical and genetic characteristics of a Chinese boy with infantile hypophosphatasia.

Methods: The clinical data of the boy was carefully collected. The laboratory and radiographic examination were taken in the case. Sequencing for all the twelve ALPL exons and the flanking exon-intron junctions was performed in the proband and his parents with their genomic DNA.

Results: Two mutations were found with one missense mutation c.814C > T (p. R272C) in the proband and his father and the other deletion mutation c.1101_1103 delCTC (p.S368del) in the proband and his mother. The proband was manifested as a compound heterozygotes of the two mutations. The mutations were not detected in fifty normal controls.

Conclusion: The result suggests that the compound heterozygous mutation in ALPL is responsible for infantile hypophosphatasia in the Chinese family.