不同流域光倒刺鲃(Spinibarbus hollandi)子一代及其亲本的线粒体COI 基因遗传变异分析

对2 组光倒刺鲃(Spinibarbus hollandi)杂交子一代(长江♀×北江♂子一代, 北江♀×长江♂子 一代)及其亲本(北江♀、♂, 长江♀、♂)的线粒体COI 基因序列进行了分析。在18 个样品中共检测到 8 个单倍型和35 个核苷酸多态位点。通过序列差异分析和遗传距离比较发现, 核苷酸序列同源性在 98.1%-99.9%之间, 遗传分化不明显。杂交子一代的5 个单倍型与其母本的2 个单倍型的核苷酸同 源性在99.4%-99.8%之间。而与父本的同源性分别为98.5%、98.2%、98.2%、98.4%、98.1%.实验 结果表明两种杂交子一代的线粒体 COI 基因严格遵循母性遗传规律。

GENETIC VARIABILITY OF mtDNA COI GENES IN SPINIBARBUS HOLLANDI

To identify phylogenetic variability in Spinibarbus hollandi hybrids from two populations, their mitochondrial cytochrome oxidase subunit I (COI) gene fragments were amplified in PCR (Polymerase Chain Reaction), of which a 1551-bp base-pair nucleotide sequence was examined. Eighteen samples were divided into 6 groups, from which 8 haplotypes and 35 nucleotide polymorphic loci COI gene fragments were recognized and they shared high similarities from 98.1% to 99.9% in nucleotide sequence revealed by sequence divergence and genetic distance analyses, indicating no significant genetic difference among these groups. In five COI haplotypes of the first-generation hybrids, the similarity was 99.4%-99.8% to the female parents and 98.1%-98.5% to the male ones. Therefore, the hybrids inherited more from their maternal parent in mitochondrial COI genes, following strictly the rules of maternal inheritance.