IDENTIFICATION OF A NOVEL WASP GENE MUTATION IN CHINESE TWIN BOYS WITH WISKOTT-ALDRICH SYNDROME

Jiang LP¹, Yang XQ¹, Xu YH¹, Wang LJ¹, Lau YL², Chan KW²

¹ Department of Paediatrics, Children’s Hospital, Chongqing University of Medical Sciences, Chongqing, China

² Department of Pediatrics, The University of Hong Kong, Hong Kong

Objective: To identify the types of Wiskott-Aldrich Syndrome protein (WASP) gene mutations in Chinese twin boys suffering from Wiskott-Aldrich syndrome.

Methods: Based on classical Wiskott-Aldrich syndrome (WAS) clinical manifestations including thrombocytopenia, eczema, and recurrent infections; abnormal immunologic findings; and typical scanning electron micrographs, the WASP gene of Chinese aged 9 months twin boys and their mother were examined by PCR based mutation detection using automatic DNA sequence analysis.

Results: For the twin boys, a novel C deletion (nucleotide 950delC according to the position of coding region) was detected in 5' region of exon 10 of WASP gene by sequencing analysis using sense and antisense primer separately. The predicted consequence of the C deletion involves frameshift mutation after H317 and premature stop at 444 (H317fsX444). For their mother, sequencing result showed that she is a carrier having one normal and one mutated WASP gene.

Conclusions: The experiment showed that the mutated genes of twin boys were inherited from their mother. The predicted frameshift mutation and premature termination in Chinese twin boys may affect the normal function of WASP, and it may be responsible for the severe thrombocytopenia and immunodeficiency.

Key words: Wiskott-Aldrich syndrome; Wiskott-Aldrich syndrome protein; Mutation; Carrier

1830