Abstract
Objective: X-linked hypophosphatemic (XLH) rickets is caused by inactivating mutations in the PHEX gene, which encodes a metalloprotease that cleaves small peptide hormone. So far there are only a few reports on XLH patients from China. In the present study, we report on six XLH patients from one family. A PHEX missense mutation was found in exon 22, and a literature review on the mutations of Chinese patients was undertaken.
Case description: The family included six XLH patients with five females and one male (the proband). All the patients showed a low serum phosphorus, increased blood alkaline phosphatase and normal calcium levels. Mutation analysis revealed a PHEX mutation in exon 22 (c.2237G>A). In total, 15 PHEX mutations have been reported in Chinese populations at this time.
Conclusion: These data extend the spectrum of mutations in the PHEX gene in Chinese populations.
Conflict of interest statement
Authors’ conflict of interest disclosure: The authors have no conflict of interest to declare.
Funding: This article was partly supported by the National Natural Science Foundation of China (81172681), Family Planning Commission of Zhejiang Province (2010[78]), Zhejiang Province innovation team for early screening and intervention of birth defects (2010R50045) and Hall of Zhejiang Province Science and Technology (2011C33G2010350).
Contributors: L Yang performed the laboratory analysis and data collection of the patients and wrote the first edition of the paper; J Yang performed the laboratory analysis. X Huang is the guarantor of the study and in charge of the diagnosis and treatment of the patients. All authors approved the final version of the paper.
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