Litt M, Luty J A
Department of Biochemistry, Oregon Health Sciences University, Portland 97201.
Am J Hum Genet. 1989 Mar;44(3):397-401.
The human genome contains approximately 50,000 copies of an interspersed repeat with the sequence (dT-dG)n, where n = approximately 10-60. In humans, (TG)n repeats have been found in several sequenced regions. Since minisatellite regions with larger repeat elements often display extensive length polymorphisms, we suspected that (TG)n repeats ("microsatellites") might also be polymorphic. Using the polymerase chain reaction to amplify a (TG)n microsatellite in the human cardiac actin gene, we detected 12 different allelic fragments in 37 unrelated individuals, 32 of whom were heterozygous. Codominant Mendelian inheritance of fragments was observed in three families with a total of 24 children. Because of the widespread distribution of (TG)n microsatellites, polymorphisms of this type may be generally abundant and present in regions where minisatellites are rare, making such microsatellite loci very useful for linkage studies in humans.
人类基因组包含大约50,000个散布重复序列，其序列为(dT-dG)n，其中n约为10至60。在人类中，已在多个测序区域发现了(TG)n重复序列。由于具有较大重复元件的微卫星区域通常表现出广泛的长度多态性，我们推测(TG)n重复序列（“微卫星”）可能也具有多态性。我们使用聚合酶链反应扩增人类心肌肌动蛋白基因中的(TG)n微卫星，在37名无关个体中检测到12个不同的等位基因片段，其中32人为杂合子。在三个共有24名儿童的家庭中观察到片段的共显性孟德尔遗传。由于(TG)n微卫星分布广泛，这种类型的多态性可能普遍丰富，并且存在于微卫星罕见的区域，使得此类微卫星位点在人类连锁研究中非常有用。
