应用类核沉降法,分析了三个着色性干皮病家系中35名成员外周血淋巴细胞在紫外线(2.5μJ/mm~2)照射和MNNG(2μg/mI)损伤后DNA修复能力。结果表明,6名XP患者和9名杂合子DNA损伤后20小时尚不能完成修复,他们11小时DNA修复率均值分别为UV,0.61±0.13,0.59±0.15和MNNG,0.44±0.15,0.46±0.16,与家系中10名非血缘亲属正常人DNA修复率均值为UV,0.96±0.07,MNNG,0.71±0.07相比,差异非常显著(Ρ<0.01),而XP患者和杂合子DNA修复率则无显著性差异(Γ>0.05)。提示,类核沉降技术可能为XP家系中杂合子成员检出提供一种有希望的方法。 Using nuclear subsidence method, the ability of DNA repair of peripheral blood lymphocytes of 35 members in three pigmented susceptible xerophthalmia pedigrees after UV irradiation (2.5μJ / mm ~ 2) and MNNG (2μg / ml) was analyzed. The results showed that six XP patients and nine heterozygous DNA could not be repaired 20 hours after DNA damage. The average DNA repair rates at 11 hours were UV, 0.61 ± 0.13, 0.59 ± 0.15 and MNNG, 0.44 ± 0.15 and 0.46 ± 0.16 (P <0.01), but no difference was found between XP patients and heterozygous DNA repair rate (P <0.01). The mean DNA repair rates of normal non-kin relatives in the family were UV, 0.96 ± 0.07, MNNG, 0.71 ± 0.07 Significant difference (Γ> 0.05). It is suggested that nuclear subsidence technology may provide a promising method for the detection of heterozygous members in XP pedigree.