Although two species of bottlenose dolphins (Tursiops spp.) in Chinese waters have been recognized, their pattern of genetic variation is unclear at present. In the present study, 424-bp of the mitochondrial control region from 30 bottlenose dolphins collected in Chinese waters were sequenced. Fortyseven variable sites were identified from these sequences, and 9 and 11 haplotypes were defined respectively for truncatus-and aduncus-type, two morphotypes previously recognized for bottlenose dolphins in Chinese waters. These haplotypes were combined with published mitochondrial control region sequences of other bottlenose dolphins from Chinese, Indonesian, Australian, and Atlantic waters etc. Sequence variability comparison and phylogenetic reconstruction using neighbor joining (NJ) and maximum likelihood (ML) algorithms exclusively supported the separation of haplotypes into two monophyletic clades, each of which corresponds to truncatus-and aduncus-type. This provided strong support to separate the two morphotypes into respective species, T. truncatus and T. aduncus. No shared haplotype was found between Tursiops species, and four fixed diagnostic site differences between them were identified. All samples from the northern part of Chinese waters, i. e. the Yellow Sea and the northern East China Sea, were genetically identified as T. truncatus exclusively, whereas most samples from the southern part of Chinese Waters, i.e. the southern part of the East China Sea, the Taiwan Straits, the South Chinese Sea, and the Gulf of Beibuwan, were identified as T. aduncus, but with both species overlapping in the Taiwan Strait. This genetic pattern was congruent with the distribution pattern of Tursiops as previously revealed by morphological and ecological evidences. Although the distribution of the two species overlapped in the Taiwan Strait (and maybe adjacent waters), there was no evidence of genetic interchange between them, indicating reproductive isolation. The present study strongly argues for treating the two bottlenose dolphin morphotypes/species as separate management units in making up conservation measures, but further study on the intraspecific structure using multiple molecular marker is also urgent for effective conservation.

通过猪等的C-mos基因保守区序列设计了用于扩增鲸类c-mos基因的引物。应用此引物扩增并测定了齿鲸类5个科12个种546 bp的c-mos基因编码区序列。结果表明鲸类的c-mos基因遗传变异水平较低。在系统发生重建中，同科的物种聚为单系，但不能很好地解决科下亚科间的关系，提示c-mos,基因仅适于鲸类科级以上阶元的系统发生研究。

测定了采自浙江省瑞安市的一头须鲸类标本的线粒体DNA（mitochondrial DNA，mtDNA）细胞色素b（cytochrome b, cyt b）基因369 bp和控制区（control region）933 bp的序列，通过与已发表的须鲸类同源序列比对，发现与西太平洋和日本水域的布氏鲸的cyt b基因和控制区分别有6.78%～7.05%和13.30%<14.40%的序列差异，而与来自所罗门群岛的的布氏鲸之间cyt b基因的序列完全相同，控制区的序列也仪相差一个碱基（0.28%）。提示与邻近的西太平洋和日本海的普通布氏鲸在遗传上有显著区别，而可能与所罗门群岛的布氏鲸为同一种，即小布氏鲸（Balaenoptera edeni）。同时表明，应用分子生物学手段来进行鲸肉及其制品的种类鉴定是可行和有效的。

主要组织相容性复合体（major histocompatibility complex, MHC）是脊椎动物体内与免疫应答调节密切相关的一个基因家族，是基因组中多态性最丰富的区域。通过MHC的遗传变异分析可以提供物种的遗传多样性水平、进化历史和种群动态，以及种群遗传结构等信息，并在濒危物种饲养繁殖种群的遗传管理中有重要应用。

简要介绍了mtDNA的PCR直接测序、微卫星microsatellite DNA分型、组织相容性复合体（major his-tocompadbility complex. MHC）分析等DNA分子标记技术在鲸类遗传变异、种群结构、进化历史、个体识别、亲缘鉴定及系统分类等保护遗传学领域的应用。