藏族群体Y染色体14个短串联重复序列基因座遗传多态性

目的调查藏族Y染色体上14个短串联重复序列基因座及单倍型的遗传多态性。方法应用AmpFISTRYfilerTM PCR Amplification kit进行复合PCR扩增,自动基因分析仪电泳检测126名藏族男性无关个体血样。结果在14个基因座中共检出121个等位基因,基因多样性分布在0.4104(DYS391)至0.9489(DYS385a,b)之间,除了DYS391以外,其余等位基因频率多样性均大于0.5。由14个基因座组成的Y染色体单倍型系统单倍型有105种,单倍型频率多样性0.9998。结论上述14个Y-短串联重复基因座在藏族群体中具有较好的多态性,单倍型具有很高的遗传多态性。     

Y-chromosome Lineages from Portugal, Madeira and Açores Record Elements of Sephardim and Berber Ancestry

A total of 553 Y‐chromosomes were analyzed from mainland Portugal and the North Atlantic Archipelagos of Açores and Madeira, in order to characterize the genetic composition of their male gene pool. A large majority (78–83% of each population) of the male lineages could be classified as belonging to three basic Y chromosomal haplogroups, R1b, J, and E3b. While R1b, accounting for more than half of the lineages in any of the Portuguese sub‐populations, is a characteristic marker of many different West European populations, haplogroups J and E3b consist of lineages that are typical of the circum‐Mediterranean region or even East Africa. The highly diverse haplogroup E3b in Portuguese likely combines sub‐clades of distinct origins. The present composition of the Y chromosomes in Portugal in this haplogroup likely reflects a pre‐Arab component shared with North African populations or testifies, at least in part, to the influence of Sephardic Jews. In contrast to the marginally low sub‐Saharan African Y chromosome component in Portuguese, such lineages have been detected at a moderately high frequency in our previous survey of mtDNA from the same samples, indicating the presence of sex‐related gene flow, most likely mediated by the Atlantic slave trade.     

The Y-chromosomal Heritage of the Azores Islands Population

The Azores, a Portuguese archipelago located in the north Atlantic Ocean, had no native population when the Portuguese first arrived in the 15th century. The islands were populated mainly by the Portuguese, but Jews, Moorish prisoners, African slaves, Flemish, French and Spaniards also contributed to the initial settlement. To understand the paternal origins and diversity of the extant Azorean population, we typed genomic DNA samples from 172 individuals using a combination of 10 Y‐biallelic markers (YAP, SRY‐1532, SRY‐2627, 92R7, M9, sY81, Tat, SRY‐8299, 12f2 and LLY22g) and the following Y‐chromosomal STR systems: DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393 and DYS385. We identified nine different haplogroups, most of which are frequent in Europe. Haplogroup J* is the second most frequent in the Azores (13.4%), but it is modestly represented in mainland Portugal (6.8%). The other non‐European haplogroups, N3 and E3a, which are prevalent in Asia and sub‐Saharan Africa, respectively, have been found in the Azores (0.6% and 1.2%, respectively) but not in mainland Portugal. Microsatellite data indicate that the mean gene diversity (D) value for all the loci analysed in our sample set is 0.590, while haplotype diversity is 0.9994. Taken together, our analysis suggests that the current paternal pool of the Azorean population is, to a great extent, of Portuguese descent with significant contributions from people with other genetic backgrounds.     

中国南方汉族群体九个短片段长度Y-STR基因座的遗传多态性及其法医学应用

目的研究中国南方汉族群体中，扩增产物片段长度在180bp以下的9个Y染色体的短串联重复（Y-short tandem repeal，Y-STR）基因座的遗传多态性，并用于法医学鉴定。方法采用PCR复合扩增和基因测序仪荧光检测方法，检测213个无关男性个体，调查南方汉族的9个Y-SIR基因座的等位基因频率和单倍型频率，并对84对真父子和36对非父子的亲子鉴定样本进行检测。结果213个无关男性个体中，DYS426基因座检出3个等位基因，DYS393、DYS460、DYS391和DYS389 Ⅰ基因座均检出了5个等位基因，DYS456基因座检出6个等位基因，H4和DYS388基因座检出7个等位基因，DYS458基因座检出8个等位基因。除DYS426基因座的基因多样性（gene diversity，GD）值（0．1489）较低外，其余8个基因座的GD值介于0．5064～0．9133。9个Y-SIR基因座的单倍型共有178种，其中154种单倍型仅出现1次，单倍型多样性达0．9983。在84对真父子中，未观察到基因座突变。检测36对非父子，有2个Y-STR基因座排除的案例有2例（5．56％）；有3个和3个以上的Y-STR基因座可以排除父子关系的案例为33例（91．67％）；9个Y-SIR基因座不能排除父子关系的有1例。结论9个Y-SIR基因座具有丰富的遗传多态性，该短片段长度Y-STR基因复合荧光扩增系统可用于法医学个体识别和亲子鉴定。     

男性不育症精子发生相关基因缺陷的筛查研究

目的:探讨男性不育患者精子发生相关基因缺陷与精子生成的关系。方法:应用多重聚合酶链反应(PCR)扩增分析方法对149例男性不育症患者及100例有正常生育能力的男子进行Y染色体上相关基因检测和常规外周血染色体核型分析。结果:不育症组有11例存在着Y染色体上不同基因片段的微缺失,缺失率为7.38％,染色体异常核型发生率为14.09％;而正常对照组均未发现相应部位的缺失,异常核型发生率为2％。11例存在Y染色体上不同基因片段微缺失者只有1例合并有异常核型,说明两者之间无相关性。结论:提示Y染色体微缺失是引起男性不育的一个重要原因,在进行单精子卵泡浆内注射(ICSI)时应进行Y染色体微缺失的分子检测,以免所生的男性后代亦有与其父亲相同原因的不育问题。     

Low number of Y-chromosome deletions in infertile azoospermic men at a Swedish andrology centre

Recent studies have strongly indicated that at least three regions [azoospermia factor (AZF) a-c] on the long arm of the Y-chromosome code for factors involved in spermatogenesis. In order to reveal the prevalence of microdeletions in these regions in a Swedish population, 192 men consecutively referred to our andrology unit due to infertility and showing oligozoospermia (n=53) or azoospermia (n=139) but no obstruction or hormonal disturbances, were investigated. For this study we used a multiplex polymerase chain reaction (PCR) method including 13 pairs of primers divided into five different primer mixes. It was found that four men, all with azoospermia, had deletions including part of the AZFb region and probably the entire AZFc region. Testis biopsies showed different morphology ranging from absence of germ cells to hypospermatogenisis. Of special interest was one patient that was first investigated 10 years ago due to primary infertility and oligozoospermia. Today he has developed azoospermia. It is concluded that the number of patients with microdeletions on the Y chromosome is rather low (less than 3% in highly selected azoospermic men) in our study compared to a number of other studies in which a 1-55% incidence have been reported. It is possible that ethnic differences, selection criteria and methodological aspects can contribute to the difference between the present and previous studies.     

温州永嘉汉族人群3个Y-STR基因座的遗传多态性研究

目的研究3个Y染色体STR基因座及其单倍型在温州永嘉人群中的遗传多态性分布,获得相应的群体遗传学数据。方法用复合扩增的方法扩增DYS435、DYS436和DYS4373个基因座,利用聚丙烯酰胺凝胶电泳及银染显带技术进行分型,检测140名无关男性个体单倍型分布。结果3个基因座在该群体中分别检出3、3、4个等位基因,GD值分别是0.5100,0.1490,0.4056,观察到11种单倍型,其单倍型的变异度为0.7042。结论Y-STR基因座复合扩增体系和建立的Y染色体STR数据库,在法医学鉴定中有帮助意义。     

Hypervariable polymorphism of autosomal origin detected by the Y-chromosome derived probe,pHY10

A recombinant DNA probe (pHY10) hybridizing specifically to human DNA family DYZ1, 3,000 copies of which are present on the long arm of the Y chromosome, was used for probing human genome DNA digested with various restriction enzymes. To our surprise, the probe detected a hypervariable polymorphism of autosomal origin in human DNA when digested withTaqI. None of other 12 restriction enzymes revealed polymorphic patterns. Codominant segregation of the polymorphism was established in family studies. This probe has been widely used in the detection of the Y chromosome. Its ease of availability as well as highly discriminating polymorphic pattern makes it potentially very useful for forensic and human genetic purposes.     

Rapid screening of the Y chromosome in idiopathic sterile men, diagnostic for deletions in AZF, a genetic Y factor expressed during spermatogenesis

Summary. A rapid molecular screening programme has been established for the long arm of the human Y chromosome in Yq11 in order to quickly detect small interstitial deletions in this chromosome region. They have been observed in idiopathic sterile males with azoospermia and a severe oligozoospermia and are therefore indicative for deletion of AZF gene sequences. AZF (i.e. azoospermia factor) is a genetic factor located in Yq11 which controls human spermatogenesis. The screening programme is based mainly on a multiplex PCR approach using a series of Y-specific primers amplifying single DNA loci in Yq11. The order of all Y-DNA loci can be unequivocally arranged along the whole long Y arm. Therefore, any detected deletion can be quickly mapped in relation to the proposed position of AZF. Benefits and pitfalls of this new diagnostic Y screening method will be discussed.     

Human Y-chromosomal STR types in north Thailand

A north Thai Y-haplotype database consisting of the loci DYS19, DXYS156-Y, DYS390, DYS391, DYS392, DYS393, and the four subsegments of DYS389 is presented. We observed 44 Y-types in 50 unrelated Thais, and the haplotype diversity was calculated to be 97.36%. No Y-types were shared with a sample of 55 Japanese, but 3 matches were found in a sample of 61 Han Chinese, and there was one Thai-German match in a larger west German sample (n = 179).