10个中国汉族寻常型鱼鳞病家系的FLG基因突变分析

Mutation analysis of FLG gene in 10 Chinese families with ichthyosis vulgaris

目的对10个寻常型鱼鳞病（ichthyosisvulgaris，IV）家系的FLG基因进行突变检测，并分析中国汉族人IV患者FLG基因的突变热点。方法用聚合酶链反应扩增10个IV家系的所有患者及正常成员FLG基因的全部外显子，对扩增产物直接进行DNA测序检测突变，同时选取100名无亲缘关系的正常人作为对照。结果在7个家系中发现了3种FLG基因的致病突变，包括C．3321delA、C．5757delccAG和C．8138C〉T（P．$2706X），其中有两例患者的突变类型为3321delA的纯合突变，在另外3个家系中未发现FLG基因的突变。所有家系的正常成员和100名正常对照均未发现c．5757delCCAG和C．8138C〉T（P．S2706X），而在2名正常对照中发现其携带C．3321delA杂合突变。结论在中国汉族IV家系检测到3种FLG基因的突变类型，其中C．332ldelA是最常见的突变类型（46．9％）。首次发现C．5757delCCAG和C．8138C〉T（P．$2706X）突变与IV相关。部分家系未检测到FLG基因突变，推测可能由其他致病基因导致。

Objective To detect FLG gene mutations in 10 families affected with ichthyosis vulgaris and to explore mutational hot spot of the FLG gene in Chinese Han population. Methods PCR and direct sequencing were carried out to identify potential mutations of the FLG gene in above families. One hundred healthy individuals were analyzed as normal controls. Results Three mutations （3321delA, 5757delCCAG and $2706X） were identified in 7 families. A homozygous mutation 3321de1A was also detected in two unrelated patients. No mutations were found in the remaining three families. Neither of the null mutations （5757delCCAG and S2706X） was found in the 100 controls. However, for 3321delA, a heterozygous mutation was also found in two of the controls. Conclusion Three FLG mutations have been identified in the selected families with ichthyosis vulgaris, and the 3321delA mutation was most prevalent （46. 9%）. Mutations 5757delCCAG and S2706X were first found in patients with ichthyosis vulgaris. Other candidate genes may underlie the disease in those without a FLG mutation.