湖北钉螺数量性状研究Ⅰ遗传变异信息的可靠性与样本量的关系

[文章编号]　100526661(2005)022*******・论著・湖北钉螺数量性状研究

.遗传变异信息的可靠性与样本量的关系

周艺彪,姜庆五,赵根明,韦建国

[摘要]　目的　探讨湖北钉螺数量性状遗传变异信息的可靠性与样本量的关系。方法　从云南大

理和湖南岳阳两地区随机抽取钉螺各60只,分别对钉螺壳形态数量性状进行测量,计算各数量性状

指标的变异系数(CV)、组间变异百分比和多样性指数。结果　CV以外唇缘厚度变异最大,肋壳钉螺

达到了20157%,光壳钉螺为14114%,其次是次螺层长度,分别12198%和11149%;肋壳钉螺有近

四分之三的性状指标CV大于光壳钉螺的,且平均CV9135%也大于光壳钉螺的7183%;肋壳钉螺

的平均多样性指数为11541,高于光壳钉螺的11220;当样本量<30,所得到的遗传变异的结果极不

可靠,随着样本量的增加遗传变异信息的可靠性也增加,当样本量>55时,所得到的遗传变异的结

果趋于稳定。结论　在湖北钉螺形态数量性状的遗传变异研究中,每个钉螺种群以分析不少于55个

钉螺标本为好。

[关键词]　湖北钉螺;数量性状;遗传多样性;样本量

[中图分类号]　R383124 [文献标识码]　A

Study on m orpholog ic quan tita tive character istics of

O nco m elan ia hup ensis .Rela tion sh ip between rel i ab il ity of

i nforma tion of genetic d iversity and sam ple size　Z hou Y ibiao,J iang Q ingw u,

Z hao Genm ing,W ei J iang uo　(D ep a rt m en t of Ep id e m iology,P ublic H ea lth S chool of F ud an

U n iversity,S hang ha i200032,Ch ina)

[Abstract]　Objective　To exp lo re the relati on sh i p betw een the reliab ility of info rm ati on of

genetic diversity and samp le size in mo rpho logic quan titative characteristics of O nco m elan ia

hup ensis.M ethods　Six ty snails(s moo th shell)from D ali C ity,Yunnan P rovince and six ty snails

(ribbed shell)from Yueyang C ity,H unan P rovince w ere samp led at random,and the mo rpho logic

quan titative characteristics of the snails w ere m easu red,and then the coefficien t of variati on,

p ropo rti on of variati on betw een the tw o group s and Shannon’s info rm ati on index w ere compu ted

respectively.Results　Among11indices of mo rpho logic quan titative characteristics,the coefficien t

of variati on of th ickness of lab ra b ri m w as the largest,and tho se of ribbed2shell and s moo th2shell

popu lati on w ere20157%and14114%respectively,and the nex t w as length of hypo2body w ho rl,

and tho se of ribbed2shell and s moo th2shell snails w ere12198%and11149%respectively.Among

11mo rpho logic quan titative characteristics indices,there w ere nearly th ree ou t of fou r indices w h ich

the coefficien ts of variati on of ribbed2shell snails w ere mo re than tho se of s moo th2shell popu lati on,

and the average coefficien t of variati on of ribbed2shell popu lati on w as also mo re than tho se of

s moo th2shell popu lati on.T he average Shannon’s info rm ati on indices of ribbed2shell and s moo th2

shell popu lati on w ere11541and11220respectively,and the fo rm er w as the b igger.W hen the

samp le size w as less than30,the resu lt of genetic diversity gained from the study w as no t very

reliab le,and w ith the increase of samp le size the reliab ility of the info rm ati on of genetic diversity

w as also augm en ted.W hen the samp le size w as mo re than55,the resu lt of genetic diversity w as

reliab le.Conclusion　In o rder to get reliab le info rm ati on of genetic variati on in the study of

[基金项目]　“十五”国家科技攻关项目(2004BA718B04)

[作者单位]　复旦大学公共卫生学院流行病学教研室(上海200032)

[作者简介]　周艺彪(1972-),男,博士。研究方向:血吸虫病流行病学与分子生物学