Abstract: Objective To analyze the clinical characteristics and genetic etiology of a case of Bernard-Soulier syndrome. Methods The clinical and molecular genetic data of a child diagnosed with BSS were reviewed. Results The patient was a 5 -year-old boy. Thrombocytopenia occurred in the newborn period, and the platelet count was maintained at ( 25 ~ 40 ) × 109 /L. Gamma globulin and hormone therapy were not effective. The expression level of platelet membrane glycoproteinⅠbα(GPⅠbα) was 42.4%, which was significantly lower than normal level. Whole exome sequencing detected two variations in the GP 1 BA gene of the child, c. 987 G>A and c. 523 _ 525 delAAC. The Sanger family verified that the variations were derived from their parents respectively and constituted a compound heterozygous variant. Conclusion The variation site of c.523 _ 525 delAAC has not been reported, which expands the BSS gene variation spectrum.

Key words: thrombocytopenia; Bernard-Soulier syndrome; next-generation sequencing, GP 1 BA gene