Veletza S V, Rogan P K, TenHave T, Olowe S A, Floros J
Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey 17033, USA.
Exp Lung Res. 1996 Jul-Aug;22(4):489-94. doi: 10.3109/01902149609046037.
Variable numbers of composite repetitive motifs are found in different individuals within intron 4 of the surfactant protein B (SP-B) gene (Biochem J. 1995;305:583). This study tests the hypothesis that the distribution of SP-B alleles differs among racial/ethnic groups. A total of 412 SP-B alleles were analyzed: 206 from Caucasian, 68 from African-American, and 138 from Nigerian individuals. Twelve groups of alleles (A-L) carrying 3 to 18 motifs were found. The distribution of the 12 alleles in the Caucasian group differs from that found in the Nigerian (p < .001) and African-American (p < .001) populations. The overall distribution of alleles between the African-American and the Nigerian populations were not statistically different. Specific alleles were also present in different proportions among the groups studied. For example, the most common allele (allele E) in all three populations is present at a significantly higher frequency in Caucasians than in the other two populations, but its frequency does not differ from the Nigerian and African-American groups. A less frequent allele, H, also differs significantly when Caucasians are compared with each of the other two populations, but the frequency of this allele is comparable between the African-American and Nigerian populations. To assess the importance of having comparable racial composition between the control and the case groups, a group of African-Americans with respiratory distress syndrome (RDS) (n = 40) was compared with the African American and the Caucasian groups studied above. No significant difference was observed between the racially matched groups but a significant difference (p = .006) was observed between the racially mixed groups. The results indicate that the distribution of SP-B alleles differs between the racial groups but not between the ethnic groups studied. Thus, racial composition of the groups under study is important when considering whether particular alleles at this locus predispose to inherited disorders.
在表面活性蛋白B（SP - B）基因的第4内含子中，不同个体存在数量可变的复合重复基序（《生物化学杂志》。1995年；305:583）。本研究检验了SP - B等位基因分布在不同种族/民族群体中存在差异这一假设。共分析了412个SP - B等位基因：206个来自白种人，68个来自非裔美国人，138个来自尼日利亚人。发现了12组携带3至18个基序的等位基因（A - L）。白种人群体中12个等位基因的分布与尼日利亚人群体（p <.001）和非裔美国人群体（p <.001）中的分布不同。非裔美国人群体和尼日利亚人群体之间等位基因的总体分布无统计学差异。在所研究的群体中，特定等位基因的比例也各不相同。例如，所有三个群体中最常见的等位基因（等位基因E）在白种人中的频率显著高于其他两个人群体，但与尼日利亚和非裔美国人群体相比其频率并无差异。一个较罕见的等位基因H，在白种人与其他两个人群体分别比较时也存在显著差异，但该等位基因在非裔美国人群体和尼日利亚人群体中的频率相当。为评估对照组和病例组之间种族构成具有可比性的重要性，将一组患有呼吸窘迫综合征（RDS）的非裔美国人（n = 40）与上述非裔美国人群体和白种人群体进行了比较。在种族匹配的群体之间未观察到显著差异，但在种族混合的群体之间观察到了显著差异（p =.006）。结果表明，SP - B等位基因的分布在种族群体之间存在差异，但在所研究的民族群体之间不存在差异。因此，在考虑该位点的特定等位基因是否易导致遗传性疾病时，所研究群体的种族构成很重要。
