Hyperphosphatasia with Mental Retardation Syndrome Due to a Novel Mutation in PGAP3

Abstract

Hyperphosphatasia with mental retardation syndrome is a heterogeneous genetic condition. Two siblings aged 5 years and 3 years were evaluated for global development delay and facial dysmorphism. A novel missense variant, c.851A>G (p.H284R, NM_033419.3), in PGAP3 was identified using whole-exome sequencing. Assays for elevated alkaline phosphatase and exome sequencing can be useful for the diagnosis of hyperphosphatasia with mental retardation syndrome.

Keywords

hyperphosphatasia with mental retardation syndrome - PGAP3 - exome sequencing - alkaline phosphatase

Note

A. S. and M. H. drafted the manuscript and analyzed the exome sequencing data. S. N. and A. G. R. are the clinicians involved in the evaluation of the patient. S. P. K. evaluated the patients and did literature search. S. B. and K. M. G. supervised the entire work. All contributors have read and approved the manuscript.

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