Hizawa N, Yamaguchi E, Furuya K, Ohnuma N, Kodama N, Kojima J, Ohe M, Kawakami Y
First Department of Medicine, School of Medicine, Hokkaido University, Sapporo, Japan.
J Med Genet. 1995 May;32(5):363-9. doi: 10.1136/jmg.32.5.363.
The genetic linkage of atopy to chromosome 11q13 through maternally derived alleles has been previously reported. Linkage analysis in Japanese families did not confirm the existence of a major gene for atopy at this locus under the model of autosomal dominant inheritance. However, we observed a significant association between serum total IgE levels and genetic markers at this locus both in 14 Japanese atopic families and in 120 unrelated Japanese subjects. We detected eight alleles at the D11S97 locus and eight alleles in the CA/GT repeat region in the fifth intron of the Fc epsilon RI beta gene. A significantly increased frequency of the D11S97/PstI 0.96 kb allele was observed in the chromosomes of the subjects with high serum total IgE levels both in the family study (p < 0.001) and in the population study (p < 0.05). However, multipoint linkage analysis again did not show any evidence for the existence of a major gene regulating atopy on chromosome 11q13 with location scores to -35 under the model of maternal inheritance. Evidence against linkage was confirmed by the non-parametric linkage analysis, using the affected pedigree member method. Also, there was no substitution of isoleucine for leucine in the fourth transmembrane domain of Fc epsilon RI beta (Leu181), which was reported to be responsible for a subset of atopy in the British population. Therefore, the association of serum total IgE levels with chromosome 11q13 indicates that a gene or genes at this locus may contribute to the expression of high IgE levels in the Japanese population as well as in the British population, but the heterogeneity of the genetic regulation of serum total IgE levels is evident between the two populations.
先前已有报道称,特应性通过母系遗传等位基因与11号染色体q13区域存在遗传连锁。在日本家庭中进行的连锁分析未证实,在常染色体显性遗传模式下该位点存在特应性的主要基因。然而,我们在14个日本特应性家庭和120名无亲缘关系的日本受试者中均观察到,血清总IgE水平与该位点的遗传标记之间存在显著关联。我们在D11S97位点检测到8个等位基因,在FcεRIβ基因第五内含子的CA/GT重复区域检测到8个等位基因。在家族研究(p<0.001)和群体研究(p<0.05)中,血清总IgE水平高的受试者染色体上,均观察到D11S97/PstI 0.96 kb等位基因的频率显著增加。然而,多点连锁分析再次未显示任何证据支持,在母系遗传模式下11号染色体q13区域存在调控特应性的主要基因,其定位分数为-35。使用受累家系成员法进行的非参数连锁分析,证实了反对连锁的证据。此外,在FcεRIβ的第四个跨膜结构域(Leu181)中,未观察到异亮氨酸取代亮氨酸的情况,据报道,在英国人群中该情况与一部分特应性有关。因此,血清总IgE水平与11号染色体q13区域的关联表明,该位点的一个或多个基因可能在日本人群和英国人群中,均对高IgE水平的表达有作用,但血清总IgE水平遗传调控的异质性在这两个人群之间很明显。