Abstract: Objective　To explore the clinical and gene variation characteristics of phytosterolemia caused by ABCG5 gene mutation. Method　The clinical data of phytosterolemia caused by ABCG5 gene mutation in a child was retrospective analyzed. Results　A boy, aged 1 year and 3months old, began to appear linear xanthan in the skin folds of wrist and ankle joints at about 4 months old, and then gradually aggravated. Serum sterol spectrum revealed that the levels of rapeseed sterol and dihydrocholesterol increased significantly. Whole exon detection of ABCG5 gene showed splice site mutation at c.904+1(IVS7) G>A and non-coding region mutation at c.-76 (exonl) C>T. After strictly limiting plant sterol intake, reducing animal sterol intake and treating with cholestyramine for 40 days, the level of plant sterol was significantly lower than before. Conclusion　ABCG5 mutation can cause phytosterolemia. Timely diagnosis, drug treatment and diet control can improve the prognosis.

Key words: 　phytosteroemia;　ABCG5 gene;　cholestyramine