One patient with perinatal hypophosphatasia due to mutations in the tissue-nonspecific alkaline phosphatase gene / 中华内分泌代谢杂志

ABSTRACT

Objective:To explore the clinical and genetic characteristics of a Chinese baby with perinatal hypophosphatasia (HPP) and his parents for better understanding of the disease.Methods:The clinical data of the patient with HPP was carefully collected. The laboratory and radiographic examination data were taken for this baby patient. Sequencing for all the twelve tissue-nonspecific alkaline phosphatase(ALPL) exons and the flanking exon-intron junctions were performed in the proband and his parents with their genomic DNA from peripheral blood.Results:The blood level of alkaline phosphatase was decreased in this patient while serum calcium level was increased. His bone revealed chondrodysplasia-like change. Compound heterozygous mutations were found in the proband, with c. 346G>A(p.A116T) in exon 5 and c. 1171C>T(p.R391C) in exon 10. His father and mother were without clinical manifestation while respectively carried c. 346G>A(p.A116T and c. 1171C>T(p.R391C) missense mutations, suggesting an autosomal recessive inheritance in this family.Conclusion:Perinatal HPP has a high mortality rate. Skeletal deformities, hypercalcemia, and low level of ALP are important in the differential diagnosis of perinatal HPP.