中国境内黑腹果蝇Drosophilamelanogaster群体由对P族转座子敏感性形成的梯度分布

The Distributional Clines in P Susceptibility Causing by the P Family Transposable Element in Drosophila melanogaster Population of China

中国境内从新疆、西藏到沿海，包括中国台湾、海南及崇明３大岛，共取样７０多个地区品系。遗传分析和单个果蝇的ＤＮＡ压印分子杂交分析后确定，在中国境内该果蝇主要是Ｍ型。虽在遗传分析中，除沿海地区外，大多表现很高的对Ｐ敏感性（高达１００％左右），但在分子检测中都带有Ｐ因子的Ｐ１和Ｐ２的片段，故尔确定为Ｍ＇型。而大连半岛、崇明岛和台中３地区的Ｐ活性较高，它们分别是：１１％，１８％和２８％，为Ｑ型（台湾的其他地区均表现Ｍ＇型特徵）。从由纬度来划分的４个区域进行比较，找出了两条分界线，东经１１５°线和北回归线。（１）东经１１５°，将沿海与内陆分开。沿海岸由东向西，可分辨出纵行推进的、逐步过渡的３条线：最东的１线，对Ｐ敏感性非常弱，有７个品系是０，１５个品系在１０％以下，但在Ｐ活性的特征上都很低，不超过１０％，呈中性（平均为７．２３％）。此线以西的２线，其对Ｐ敏感性略增（平均２６．６了％）。再往西的３线更为增加（平均８７％），接近最高值；３线以西为最高，达９０％－１００％。越往西表现出越强的对Ｐ的敏感性。东经１１５°在第２和第３条线之间。（２）北回归线，从对Ｐ敏感性看来，它将东部沿海城市分为两部分。此线以南的广州、海南（海?

An extensive survey of the P family transposable element of Drosophila melanogaster in China, from the far west as Xinjiang and Xizang (Tibet) to the east coast, covered all China was provided. Strains, sampling more than 70 localities. which were collected during 1980- 1995. In the term of the PM system, the phenotypic property of it was mainly M type, including Taiwan. The molecular test determined. it was M type. There were three localities, the P activity of them were higher as Q type. They are: Dalian Peninsular. Chongming island, near Shanghai and Taizhong of Taiwan. For analyzed geographically, according to the east longitudes, grouped the country to four parts. After comparison, two dividing lines were found: 1. The East longitude of 115°, it was between Area II and Area III, see Fig.4, separating the coastal from inland. Except the P susceptibility of the northeastern three provinces was little higher, about 30.37%, the most part of the east coastal, the first line, its P susceptibility was very week. Seven strains were 0, fifteen strains were under 10%; its P activity was also low, never beyond 10%. therefore, it was appeared neutral,its average was 7.23%. That was the major neutral property of the coastal areas. The second line of little increased P susceptibility averaged about 26.67%. Then, there was the third linewas, when the line was the more westward, its P susceptibility was higher, up to 87%, closing to the highest score of minddlewest part of the country. From the cast coast to the west. there were three gradually increased P susceptibility lines pushing forward could be found. The E 115°, it was between the lines of the second and the third. 2. Besides the East Longitude of 115°, there is another natural geographic line shows its potentiality, that is the Tropic of Cancer. It divided the coastal to two parts, the localities at the south of this line, they did not show the coastal characteristic, instead of neutral or very week P susceptibility, they showed very strong P susceptibility as the inland localities strains were, They were left in the inland, Area II and their position were also there. Although the most part of the coastal areas presented the eastern property of neutral; the P susceptibility of the coastal cities located at the south of the Tropic of Cancer, that was very strong M type, which was different from that of the Tropical of Australia. At the north part of the Tropic of Capricom of Australia, there was P type.