A Novel HLXB9 Mutation in a Chinese Family with Currarino Syndrome

Introduction

Currarino syndrome (CS), first described in 1981,[1] is a congenital malformation typically associated with sacral agenesis, anorectal malformations, and a presacral mass. Patients affected by CS display a phenotypic variability, whereby the spectrum of phenotypes ranges from a severe triad to asymptomatic features.[2] [3]

A familial tendency with autosomal dominant inheritance was noted by Yates et al. in 1983.[4] Ross et al. further reported that mutations in the homeobox gene HLXB9 are the major cause of CS.[5] Mutations in the HLXB9 gene have been identified in almost all reported cases of familial CS, and in approximately 30% of patients with sporadic CS.[6]

The HLXB9 gene is essential for proper pancreatic development and for the differentiation of motor neurons in the spinal cord.[7] [8] It has 3 exons and encodes a 403-amino acid transcription factor HB9 protein. The HB9 protein contains a homeodomain preceded by a highly conserved 82-amino acid domain and a poly-alanine region.[9]

In this article, we report a new HLXB9 gene mutation identified in a Chinese family with members suffering from CS, together with the clinical characteristics of the affected individuals.

• References

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