The degree of polymorphism, i.e., DNA sequence divergence, of short AT-rich tandemly arranged simple sequence repeats at or near promoters and 5′- untranslated regions of mRNA may quantitatively regulate transcription of tissue-specific genes. Less polymorphic repeats allow greater gene expression. Preferential binding of hypophosphorylated H1 histone to these repeats may diminish binding of transcription factors. Preferential binding of hypophosphorylated high mobility group chromatin proteins would increase this binding. Shorter simple sequence repeats have undergone fewer point mutations than longer repeats, hence they are less polymorphic and more conserved. The role of transcribed simple sequence repeats in frog embryo germ layer determination is considered.

中文翻译：

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简单序列重复的多态性可以定量调节基因转录

位于或靠近启动子和mRNA 5'-非翻译区的富含AT的短串联排列的简单序列重复的多态性程度，即DNA序列分歧，可以定量调节组织特异性基因的转录。较少的多态性重复允许更大的基因表达。低磷酸化 H1 组蛋白与这些重复序列的优先结合可能会减少转录因子的结合。低磷酸化高迁移率组染色质蛋白的优先结合将增加这种结合。较短的简单序列重复比较长的重复经历更少的点突变，因此它们的多态性更少并且更保守。考虑了转录的简单序列重复在青蛙胚胎胚层测定中的作用。