Genetic analysis of phytosterolemia

两名患有多发性黄瘤、间歇性关节炎和血小板减少症的女性被诊断为植物甾醇血症，一种常染色体隐性脂质沉积病，基于其血清β-谷甾醇、菜油甾醇和谷甾烷醇浓度升高。该基因位于染色体2 p21的微卫星标记D2 S1788和D2 S1352之间，距离为18 centiMorgan。我们用该位点周围的16个微卫星标记对患者及其家庭成员进行基因分型。对其中一个家系的纯合性定位结果表明，该基因位于D2 S2328和D2 S1352之间的12.6centiMorgan的距离内。我们将遗传距离缩短了5.4厘摩。

Two women with multiple xanthomas, intermittent arthritis and thrombocytopenia were diagnosed as phytosterolemia, an autosomal-recessive lipid storage disease, based on their increased serum concentrations of β-sitosterol, campesterol and sitostanol. The gene responsible for this disease is located within the distance of 18 centiMorgan, between microsatellite markers of D2S1788 and D2S1352 at chromosome 2p21. We genotyped the patients and their family members with sixteen microsatellite markers around this locus. The results from the homozygosity mapping of one family suggested that the gene was located within the distance of 12.6 centiMorgan between D2S2328 and D2S1352. We have shortened the genetic distance by 5.4 centiMorgan.