Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
PLoS One. 2011 Jan 27;6(1):e15656. doi: 10.1371/journal.pone.0015656.
A total of 172 persons from nine South Amerindian, three African and one Eskimo populations were studied in relation to the Paired box gene 9 (PAX9) exon 3 (138 base pairs) as well as its 5'and 3'flanking intronic segments (232 bp and 220 bp, respectively) and integrated with the information available for the same genetic region from individuals of different geographical origins. Nine mutations were scored in exon 3 and six in its flanking regions; four of them are new South American tribe-specific singletons. Exon3 nucleotide diversity is several orders of magnitude higher than its intronic regions. Additionally, a set of variants in the PAX9 and 101 other genes related with dentition can define at least some dental morphological differences between Sub-Saharan Africans and non-Africans, probably associated with adaptations after the modern human exodus from Africa. Exon 3 of PAX9 could be a good molecular example of how evolvability works.
共研究了来自九个南美印第安人、三个非洲人和一个爱斯基摩人群体的 172 个人，涉及配对盒基因 9（PAX9）外显子 3（138 个碱基对）及其 5'和 3'侧翼内含子片段（分别为 232 个碱基对和 220 个碱基对），并结合了来自不同地理起源个体的同一遗传区域的可用信息。在外显子 3 中发现了 9 个突变，在其侧翼区域发现了 6 个突变；其中有 4 个是新的南美部落特异性单核苷酸多态性。外显子 3 的核苷酸多样性比其内含子区域高出几个数量级。此外，PAX9 及其 101 个其他与牙齿有关的基因中的一组变体可以定义撒哈拉以南非洲人和非非洲人之间至少一些牙齿形态差异，这可能与现代人离开非洲后的适应有关。PAX9 的外显子 3 可以作为一个很好的分子例子，说明进化的可塑性是如何发挥作用的。
