利用古代DNA信息研究黄河流域家猪的起源驯化

Exploring the origin of domesticated pigs in the Yellow River area using information from ancient DNA

猪的起源驯化一直是人们关注的科学问题.古DNA技术可为家猪起源驯化研究提供更为直接的科学证据.已有研究表明,中国家猪在黄河中下游流域曾发生过独立的驯化过程,但黄河上游的古代猪样品研究尚属空白.本研究选取黄河流域的3个遗址出土的14个古代猪样本为实验材料,通过DNA提取、PCR扩增和DNA测序,结合现代不同品种家猪、野猪及黄河中下游猪古DNA序列信息,系统分析了我国家猪的起源驯化关系.实验共获得5个古代猪样本mtDNAD-loop 179bp的DNA序列,包括2个湖北青龙泉遗址样本和3个青海喇家遗址样本.序列比对分析发现,湖北青龙泉遗址与青海喇家遗址的样本分别共享1种单倍型.结合现代不同品种猪、野猪及黄河中下游猪古DNA序列信息,发现湖北青龙泉遗址样本与山西贾湖遗址的部分古代样本具有相同的单倍型,青海喇家遗址的样本与山西高红遗址和陶寺遗址的另外部分样本具有相同的单倍型,并且这2个单倍型对应于中国现代猪种的2个主单倍型,说明黄河上游与中下游的猪具有相同的驯化中心.本研究填补了黄河流域上游古代猪DNA研究的空白,为中国家猪的起源驯化研究提供了新的科学佐证.

The origin of domesticated pigs is of interest to the general public. Technology to analyze ancient DNA can provide direct scientific evidence to address this question. It has been reported that modern Chinese pigs were domesticated in an independent pattern in the area of the middle and lower reaches of the Yellow River; however, ancient pig samples from the upper reaches of the Yellow River have never been tested. In this study, 14 unearthed ancient pig samples were collected from three archaeological sites in the upper and middle reaches of the Yellow River. Using DNA extraction, PCR amplification and DNA sequencing, these ancient samples were analyzed and compared with gene information from ancient pig samples from the middle and lower reaches of the Yellow River and from modern wild boars and domesticated pigs. We succeeded in generating a 179 bp sequence of mitochondrial D-loop from five ancient pig samples respectively, including three samples from the Qinglongquan archaeological site in Hubei Province and two samples from the Lajia archaeological site in Qinghai Province. Sequence alignment analysis indicated that ancient samples from Qinglongquan and Lajia were sorted into different haplotypes. Compared with previous data from ancient DNAs, modern pig breeds and wild boars, the two Qinglongquan samples shared one haplotype with one sample from the Jiahu site, and the Lajia samples shared a haplotype with four samples from the Gaohong archaeological site and with three samples from the Taosi archaeological site, which are both located in Shanxi Province. The two haplotypes were consistent with the four main types of modern Chinese pigs. The results indicate that pigs in the upper reaches of the Yellow River originated from the same domestic center as the pigs in the middle and lower reaches of the Yellow River did. These findings further our understanding of the origin of pig domestication in China.