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1.
牙齿是古代样本中最易保存下来的材料之一,因此在人类学研究中具有极为重要的价值.通过比较牙齿形态特征在群体中的频率,可揭示群体间的进化关系;而在个体层面上的遗传学研究,则可进一步揭示牙齿特征的形成机制和进化意义.本研究通过分析中国新疆维吾尔族242个个体的38项牙齿形态特征,首先确认了新疆维吾尔族的牙齿形态特征表现为欧洲群体与东亚群体的混合性状,其混合程度与群体遗传学研究结果一致.其次,通过对各项牙齿形态特征进行两两相关分析,在相关性矩阵中发现3个主要表型模块,各模块分别代表相关性较高的牙齿形态特征.其中,铲形门齿、双铲形门齿及上颌犬齿近中嵴组成了一个主要模块.最后,本研究发现遗传变异EDARV370A与上述表型模块中的牙齿形态特征均呈显著相关.对该表型模块提取复合表型因子后,EDARV370A与该复合表型因子具有显著的关联性,并可以解释18%的表型变异度.说明同一遗传因素同时影响了多项牙齿形态特征.本研究结果进一步证实了3万年前在东亚出现的遗传变异EDARV370A是产生铲形门齿这一特征的重要因素.说明东亚现代人群所具有的铲形门齿特征可能是更新世晚期以后进化的产物.  相似文献   

2.
牙齿是古代样本中最易保存下来的材料之一,因此在人类学研究中具有极为重要的价值.通过比较牙齿形态特征在群体中的频率,可揭示群体间的进化关系;而在个体层面上的遗传学研究,则可进一步揭示牙齿特征的形成机制和进化意义.本研究通过分析中国新疆维吾尔族242个个体的38项牙齿形态特征,首先确认了新疆维吾尔族的牙齿形态特征表现为欧洲群体与东亚群体的混合性状,其混合程度与群体遗传学研究结果一致.其次,通过对各项牙齿形态特征进行两两相关分析,在相关性矩阵中发现3个主要表型模块,各模块分别代表相关性较高的牙齿形态特征.其中,铲形门齿、双铲形门齿及上颌犬齿近中嵴组成了一个主要模块.最后,本研究发现遗传变异EDARV370A与上述表型模块中的牙齿形态特征均呈显著相关.对该表型模块提取复合表型因子后,EDARV370A与该复合表型因子具有显著的关联性,并可以解释18%的表型变异度.说明同一遗传因素同时影响了多项牙齿形态特征.本研究结果进一步证实了3万年前在东亚出现的遗传变异EDARV370A是产生铲形门齿这一特征的重要因素.说明东亚现代人群所具有的铲形门齿特征可能是更新世晚期以后进化的产物.  相似文献   

3.
目的 定量检测新疆维吾尔族2型糖尿病(T2DM)和糖耐量正常(NGT)人群肠道中的普拉梭菌(Faecalibacterium prausnitzii)水平。方法 提取上述人群粪便细菌总DNA后,采用16S rDNA基因实时荧光定量PCR对普拉梭菌水平进行定量检测;运用Pearson分析普拉梭菌水平与研究对象的空腹血糖(FBG)、甘油三酯(TG)、总胆固醇(TC)、体重和体重指数(BMI)的相关性。结果 (1)16S rDNA基因实时定量PCR结果显示:与新疆维吾尔族NGT组相比,普拉梭菌水平在T2DM中较低(t=2.590,P=0.014),差异有统计学意义。(2)新疆维吾尔族上述人群肠道中普拉梭菌水平与FBG呈负相关(r=‒0.434,P=0.012),体重呈负相关(r=‒0.359,P=0.044),TG呈负相关(r=‒0.410,P=0.034)。结论 Faecalibacterium prausnitzii水平在肠道中降低可能与2型糖尿病的发病有关,其机制需进一步研究探讨。  相似文献   

4.
崔娅铭 《人类学学报》2016,35(1):89-100
中面部的形态是个人识别的重要依据,并且长期以来都在各人种的形态对比研究中占有重要的地位。而中面部骨骼形态复杂,骨骼表面不规则,很难用传统的方法来进行测量和比较。本文采用基于三维表面半标志点的几何形态测量学研究东亚现代人中面部的形态及其变异范围,并与其他各大地理位置中的现代人群的中面部形态进行对比,为人类演化和对比不同人群的形态研究建立基础数据。本研究结果显示中面部形态能够大致区分各个现代人群,其中东亚现代人与除美洲印第安人以外的所有现代人的中面部形状之间都具有较为明显的差异。东亚现代人与澳大利亚和非洲的现代人中面部形状之间的差别最明显,而与欧洲和东南亚现代人的分布范围有部分重叠。东亚现代人群中面部的平均形状却具有非常明显的特点:沿着正中矢状面的结构回缩,而两侧的结构向前方和两侧突出。而其他现代人群的中面部平均形状则呈现出相反的特征,即沿着正中矢状面的结构为突出,而两侧的结构回缩的特征。这些特点在东亚发现的化石人类标本中也有很高的发生率,这表明这些中面部特征在东亚人类进化的序列是连续的,并无受到干扰的迹象。  相似文献   

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对过氧化物酶体增殖物激活受体基因(PPARG)的31个SNP位点进行群体遗传学分析,利用质谱检测技术检测PPARG基因的31个SNPs位点多态性,并根据质谱峰图判读样本目标位点基因型,统计分析31个SNP位点的基因型和等位基因的分布频率,利用x2检验确定筛选的SNP位点是否符合Hardy-Weinberg平衡定律。结果发现31个SNP位点中,23个位点的次等位基因分布频率MAF≥0.05,在新疆维吾尔族人群中具有多态性,其他8个SNP位点的MAF0.05,没显示多态性。基因型和等位基因频率在男女两组间均无统计学差异(P0.05),表明这些位点等位基因分布不存在性别差异。  相似文献   

7.
目的:为了探讨新疆维吾尔族人ApoA5基因-1131T>C基因变异的频率及对血脂水平的影响.方法:对145例经冠脉造影排除冠心病的维吾尔族患者,采用聚合酶链反应-限制性片段长度多态性分析对ApoA5基因-113IT>C多态性进行检测,比较不同基因型与个体血脂水平的关系.结果:ApoA5-1131C等位基因的频率是33%.TT、TC和CC三种基因型中,TC型与CC型的血甘油三酯(TG)水平明显高于TT型,而以CC型的TG水平最高(P均<0.05),C携带者(TC CC)较非C携带者(TT)的TG水平增高36.2%[(2.03 1.33)mmol/Lvs(1.49 1.06)mmol/L,P<0.05].结论:维族人群的ApoA5-113IT>C基因变异较常见,-1131C等位基因与血TG水平增高有关.  相似文献   

8.
应用PCR-RFLP基因分型技术,首次对我国新疆地区维吾尔族和哈萨克族2个少数民族群体的HLA-DQA1、-DQB1两个基因座的多态性进行了研究。结果显示,在DQA18个等位基因中,维族和哈族均表现为DQA1*0301最常见。最少见的DQA1等位基因,在维族中为DQA1*0401和*0601,而在哈族中为DQA1*0601;在DQB116个等位基因中,DQB1*0201和*0301在维族和哈族中均表现为最常见。在维族中未观察到DQB1*0502、*05032和*0504,在哈族中未观察到DQB1*05032、*0504和*0605等位基因。统计分析表明,维族和哈族DQA1、DQB1各等位基因的分布无显著性差异,说明维、哈族间具有较密切的亲缘关系。在以27个种族或民族的HLA-DQA1、-DQB1两基因座基因频率构建的分子系统树上,维族和哈族独立于其他群体而聚类,独处一支。维族和哈族接近蒙古人种,而离高加索人种较远。  相似文献   

9.
李雪  吴杨婧雯  俞超  周卉  徐欣  汪财生  郭斌 《广西植物》2023,43(12):2309-2318
为探究外源水杨酸(SA)对低温胁迫下火龙果幼苗形态及生理的影响,该研究以‘紫红龙’火龙果幼苗为材料,将4个不同浓度的SA(0.1、0.3、0.5、0.7 mmol·L-1)喷施叶片,48 h后4℃低温培养,于第0、第3、第6、第9天观察火龙果幼苗形态及叶片组织结构的变化,并测定叶片相对电导率、丙二醛含量、渗透调节物(可溶性糖、可溶性蛋白、脯氨酸)含量及抗氧化酶(超氧化物歧化酶、过氧化物酶、过氧化氢酶、谷胱甘肽S-转移酶)活性等生理指标。结果表明:(1)低温胁迫下,火龙果幼苗呈现0级、Ⅰ级和Ⅱ级3个冷害等级,SA处理后的火龙果幼苗出现Ⅰ级冷害和Ⅱ级冷害的株数百分率均明显降低。(2)与低温对照相比,SA处理能降低火龙果幼苗叶片相对电导率和丙二醛含量并提高渗透调节物含量和抗氧化酶活性。(3)通过对不同SA处理结果进行比较分析,发现缓解冷害症状、降低相对电导率和丙二醛含量、提高可溶性糖和脯氨酸的含量、提高超氧化物歧化酶和谷胱甘肽S-转移酶的活性均以0.3 mmol·L-1 SA效果最好,提高可溶性蛋白含量、过氧化物酶活性、过氧化氢酶活性分别以0.7、...  相似文献   

10.
目的:探讨维生素K环氧化物还原酶复合体亚单位1(VKORC1)基因rs9923231及γ-谷氨酰羧化酶(GGCX)基因rs2592551位点多态性同新疆维吾尔族和汉族人群发生心源性脑栓塞的关系。方法:选取2017年1月至2018年10月曾就诊于新疆医科大学第六附属医院神经内科的维吾尔族和汉族散发性房颤致脑栓塞患者各50例做为病例组,同时选取非心源性脑卒中维吾尔族患者50名及汉族患者150名为对照组,从外周静脉血中提取基因组DNA,采用PCR-RFLP技术检测VKORC1基因rs9923231及GGCX基因rs2592551多态性位点在不同人群中的分布。结果:维吾尔族脑栓塞组及对照组VKORC1基因rs9923231多态性位点基因型频率分布差异有统计学意义(P0.05);汉族脑栓塞组及对照组VKORC1基因rs9923231多态性位点基因型频率的分布比较差异无统计学意义(P0.05)。GGCX基因rs2592551多态位点在汉族、维吾尔族脑栓塞组及对照组的分布差异均无统计学意义(P0.05)。结论:VKORC1基因rs9923231多态性可能与新疆维吾尔族人群心源性脑栓塞的发病有关,而与汉族人群无关;GGCX基因rs2592551多态性可能与维吾尔族及汉族人群心源性脑栓塞的发病均无关。  相似文献   

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Teeth are one of the most important materials for anthropological studies because they are likely to be preserved in ancient remains.While the frequencies of dental characteristics can provide clues to the phylogeny of populations,genetic studies at the individual level can further reveal the biological mechanisms and evolutionary context of dental characteristics.In this study,by analyzing 38 dental characteristics of 242 Xinjiang Uyghur individuals,we found that(i)the dental characteristics of the Uyghurs showed evidence of admixture between European and East Asian populations.The admixture proportions were in line with those previously reported in population genetic studies;(ii)the Xinjiang Uyghur dental characteristics formed three clusters in pairwise correlation analysis.One of the main clusters consisted of characteristics including incisor shoveling,double shoveling and mesial ridge;and(iii)all the characteristics in this cluster were significantly correlated with the genetic variant EDARV370A.The extracted composite phenotypic factor was also significantly associated with EDARV370A,which explained 18%of the total phenotypic variance.This indicated a pleiotropic effect,i.e.,the same genetic factor affects a number of dental characteristics at the same time.Our results confirmed that EDARV370A,a genetic variant that first originated in East Asia about 30000 years ago,played an important role in incisor shoveling in East Asia.This finding suggested that incisor shoveling in modern humans in East Asia is likely to have appeared after the late Pleistocene.  相似文献   

13.
Previous studies have examined mid‐facial cold adaptation among either widely dispersed and genetically very diverse groups of humans isolated for tens of thousands of years, or among very closely related groups spread over climatically different regions. Here we present a study of one East Asian and seven North Asian populations in which we examine the evidence for convergent adaptations of the mid‐face to a very cold climate. Our findings indicate that mid‐facial morphology is strongly associated with climatic variables that contrast the temperate climate of East Asians and the very cold and dry climate of North Asians. This is also the case when either maxillary or nasal cavity measurements are considered alone. The association remains significant when mtDNA distances among populations are taken into account. The morphological contrasts between populations are consistent with physiological predictions and prior studies of mid‐facial cold adaptation in more temperate regions, but among North Asians there appear to be some previously undescribed morphological features that might be considered as adaptive to extreme cold. To investigate this further, analyses of the seven North Asian populations alone suggest that mid‐facial morphology remains strongly associated with climate, particularly winter precipitation, contrasting coastal Arctic and continental climates. However, the residual covariation among North Asian mid‐facial morphology and climate when genetic distances are considered, is not significant. These findings point to modern adaptations to extreme climate that might be relevant to our understanding of the mid‐facial morphology of fossil hominins that lived during glaciations. Am J Phys Anthropol 153:449–462, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

14.
通过对紧凑大穗型玉米品种陕单902的研究发现,保证适宜种植密度,增加群体总粒数是陕单902高产的基础;建立合理的群全结构和干物质生产体系,提高吐丝至成熟期的干物质生产能力是陕单902高产的关键;协调群体库源关系,提高成粒率是陕单902高产的根本。采用合理密植(不超过60000株/hm^2),宽窄行和双株栽培,保证足量氮肥和适宜氮,磷,钾配比等主要配套技术可改善大穗型玉米品种陕单902的群体库源性状,提高产量潜和。  相似文献   

15.
Down syndrome (DS), resulting from trisomy of chromosome 21, is the most common live-born human aneuploidy. The phenotypic expression of trisomy 21 produces variable, though characteristic, facial morphology. Although certain facial features have been documented quantitatively and qualitatively as characteristic of DS (e.g., epicanthic folds, macroglossia, and hypertelorism), all of these traits occur in other craniofacial conditions with an underlying genetic cause. We hypothesize that the typical DS face is integrated differently than the face of non-DS siblings, and that the pattern of morphological integration unique to individuals with DS will yield information about underlying developmental associations between facial regions. We statistically compared morphological integration patterns of immature DS faces (N = 53) with those of non-DS siblings (N = 54), aged 6-12 years using 31 distances estimated from 3D coordinate data representing 17 anthropometric landmarks recorded on 3D digital photographic images. Facial features are affected differentially in DS, as evidenced by statistically significant differences in integration both within and between facial regions. Our results suggest a differential affect of trisomy on facial prominences during craniofacial development.  相似文献   

16.
We studied the middle and inner ears of seven adult coruros (Spalacopus cyanus), subterranean and social rodents from central Chile, using free-hand dissection and routine staining techniques. Middle ear parameters that were focused on here (enlarged bullae and eardrums, ossicles of the "freely mobile type") are believed to enhance hearing sensitivity at lower frequencies. The organ of Corti was of a common mammalian type and revealed three peaks of higher inner hair cell densities. Based on a position frequency map, frequencies were assigned to the respective peaks along the basilar membrane. The first peak at around 300-400 Hz is discussed with respect to the burrow acoustics, while the peak around 10-20 kHz is probably a plesiomorphic feature. The most pronounced peak at around 2 kHz reflects the frequency at which the main energy of vocal communication occurs. The morphology of the ear of the coruro corresponds to the typical pattern seen in subterranean rodents (low frequency and low-sensitivity hearers), yet, at the same time, it also deviates from it in several functionally relevant features.  相似文献   

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The human face is a heritable surface with many complex sensory organs. In recent years, many genetic loci associated with facial features have been reported in different populations, yet there is a lack of studies on the Han Chinese population. Here, we report a genome-wide association study of 3 D normal human faces of 2,659 Han Chinese with autosegment phenotypes of facial morphology. We identify singlenucleotide polymorphisms(SNPs) encompassing four genomic regions showing significant associations with different facial regions, including SNPs in DENND1 B associated with the chin, SNPs among PISRT1 associated with eyes, SNPs between DCHS2 and SFRP2 associated with the nose, and SNPs in VPS13 B associated with the nose. We replicate 24 SNPs from previously reported genetic loci in different populations, whose candidate genes are DCHS2, SUPT3 H, HOXD1, SOX9, PAX3, and EDAR. These results provide a more comprehensive understanding of the genetic basis of variation in human facial morphology.  相似文献   

19.
Inner ear barotrauma (IEB) that is caused by acute pressure changes can often lead to permanent severe sensorineural hearing loss (SNHL). However, the mechanism that causes IEB is still unknown. In the current study, we assessed the involvement of reactive oxygen species (ROS) in IEB and the therapeutic effect of 3-methyl 1-phenyl-2-pyrazolin-5-one (edaravone), which is a free radical scavenger. To create the IEB model, guinea pigs were subjected to quick pressure changes that resulted in acute SNHL. The animals were then divided into two groups, an edaravone-treated IEB group and a non-treated IEB group that only received normal saline. Immunohistochemical analyses for 8-hydroxy-2-deoxyguanosine (8-OHdG) and 4-hydroxy-2-nonenal (4-HNE) were performed to examine the amount of oxidative DNA damage and lipid peroxidation that occurred in guinea pig cochlea. To assess the curative efficacy of edaravone, auditory brainstem response (ABR) testing was performed to evaluate auditory function. Strong immunoreactivities against 8-OHdG and 4-HNE were observed in the inner ear tissues of the non-treated IEB group. Lesser amounts of immunoreactivity were observed in the same region of the edaravone-treated IEB group as compared to the non-treated IEB group. Furthermore, ABR measurement revealed that there was a faster improvement in the threshold shift for the edaravone-treated IEB group as compared to that of the non-treated IEB group. At the final 7-week time point, the threshold shift for the edaravone-treated IEB group was significantly smaller as compared to the non-treated IEB group. These results strongly suggest that ROS is produced in the cochlea in response to acute pressure changes and that ROS plays an important role in the pathophysiology of IEB. Furthermore, edaravone treatment had a therapeutic effect on IEB-induced acute SNHL and thus, edaravone might possibly be able to be used as a therapeutic treatment for IEB.  相似文献   

20.
Paranthropus is distinctive among hominoids in its possession of a greatly thickened hard palate. Although traditionally considered a structural adaptation to counter high-magnitude masticatory stress, alternative developmental models are equally viable. Three models of palatal thickening were evaluated in this study. A mechanical model interprets palatal thickening as a compensatory response to increased instability of the midpalatal suture effected by an anterior placement of the masseteric muscle mass. This model predicts that palatal thickness is correlated with the length of the palate posterior to the masseteric tubercle. Two non-mechanical models consider the thickness of the hard palate to be structurally related to and therefore correlated with either 1) the degree to which the premaxilla overlaps the hard palate in the subnasal region or 2) the height of the posterior facial skeleton. The correlation of craniofacial variables was assessed intraspecifically in ontogenetic series of great ape and human crania. Tests of correlation were performed for each comparison using both residuals calculated from reduced major axis regression of the variable of interest against a measure of cranial size and shape ratios. A significant correlation of palatal thickness with posterior facial height in Pan suggests that the unusually thick hard palate of Paranthropus is directly related to the increased posterior facial height characteristic of this taxon. Further evaluation suggests that extreme palatal thickening in these specimens occurred by virtue of their possession of a nasal septum morphology in which the vomer extends onto the superior nasal surface of the premaxilla. Such a morphology would have constrained the palatal nasal lamina to maintain the approximate level of the premaxillary nasal lamina throughout the growth process thereby promoting palatal thickening. Am J Phys Anthropol 103:375–392, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

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