一个大型胆囊结石病家系的遗传特征及流行病学分析

目的调查某胆囊结石(胆石)病家系的遗传特点及流行病学特征。方法对该家系进行问卷调查、体格检查及实验室检查。结果该家系四代共113人(男55人,女58人),胆石患者33例(男13例,女20例),女性发病率(34.48%)高于男性(23.64%),但差异无统计学意义。和先证者有血缘关系的亲属中Ⅱ、Ⅲ代发病率52%,明显高于配偶的发病率(20%),P=0.003。先证者Ⅰ级亲属遗传度86.38%±46.46%。患者平均体重指数(25.06±2.59)kg/m2,显著高于非胆石病者平均体重指数(22.69±3.24)kg/m2,P=0.012。胆石病患者中有高血压、高血脂病史者明显多于非胆石病者,差异有统计学意义,P值分别为<0.01和0.017。糖尿病病史、饮酒习惯、喜油腻饮食在胆石病患者和非胆石病者中无差异。胆石病患者血糖平均值(5.35±0.77)mmol/L。血胆固醇和甘油三酯在胆石病患者和非胆石病者中无差异。结论该家系胆石病具有明显家族聚集性,符合常染色体显性遗传特点;性别、肥胖、高血压和高血脂病史是该家系的危险因素。     

反常性痤疮一家系nicastrin基因突变研究

目的 研究一家系2例汉族反常性痤疮患者γ分泌酶基因的突变.方法 提取家系中5名成员(2例患者、先证者父亲、2例目前未发病者)的外周血DNA,扩增nicastrin蛋白(NCSTN)、早老素(PSEN)1、早老素增强子(PSENEN)、前咽缺陷蛋白(APH1)基因所有外显子和侧翼序列进行测序,并以100例无关系健康人作为对照.同时比较先证者皮损与4个健康对照NCSTN基因mRNA表达差异.结果 检测到2例患者血样DNA存在NCSTN基因中第477位碱基发生C→A的杂合突变,即c.477C＞A,其余3名家系成员及健康对照未发现相应突变;查询美国国家生物技术信息中心网站单核苷酸多态性数据库也未发现此突变.另外,先证者皮损NCSTN mRNA水平较健康对照明显减少.结论 NCSTN基因新的无义突变c.477C＞A是该反常性痤疮家系的致病突变,并可能通过无义介导的mRNA降解途径导致该基因功能失活.     

B(A)血型分子机制研究及其家系分析

目的 研究罕见B(A)血型的血清学特性和分子机制,为B(A)血型的临床输血提供理论基础.方法 利用单克隆抗体检测1例先证者、家系成员及献血者红细胞ABO血型抗原,用标准A、B、O红细胞检测其血清中的ABO抗体.采用盐水法、凝聚胺法和抗球蛋白法进行先证者与献血者交叉配合试验.采用PCR技术扩增ABO基因的第6、7外显子序列,对先证者、家系成员、献血者标本的ABO基因外显子6、7和侧翼内含子序列进行测序分析,并对先证者标本进行单倍体序列分析.结果 先证者及其2位家系成员红细胞上有A、B抗原,同时血清中存在抗A_1抗体,血清学表型为A_2B.直接测序分析发现先证者标本第6、7外显子存在261G/del、297A/G、526C/G、657C/T、700C/G、703A/G、796A/C、803G/C、930A/G杂合,可推断为B(A)_(02)/O_(01)基因型杂合子;家系中其母亲基因型为B(A)_(02)/B_(101),外祖母为B(A)_(02)/O_(01).先证者单倍体序列分析得到2个等位基因B(A)_(02)和O_(01);与B_(101)序列相比,B(A)_(02)位第700位C>G,导致1个氨基酸改变:第234位脯氨酸变成丙氨酸.既往血清学特性为A_2B的2个献血者,1个基因型为B(A)_(02)/O_(01),另1个基因型是A_(208)/B_(101).B(A)血型先证者与这2名献血者进行交叉配血试验均相合,临床输注后无不良反应.结论 α-1,3-半乳糖基转移酶等位基因(B等位基因)700C>G突变可导致形成B(A)血型,其血清学特性显示为A_2B表型.B(A)血型临床输血相配合的供者可选择A_2B表型的献血者.     

白癜风150例家系调查

分析了１５０例白癜风病人的家族发病情况,发现１５０例白癜风患者中有家族阳性史为３９例,一级亲属共患率与二级、三级亲属共患率分别炎１４．６％、１６％、４．６７％,提示白癜风发病与遗传有密切关系。同时提出寻常型白癜风的发病因素与节段型不同,遗传因素是寻常型白癜风发病不可忽视的因素。     

一个X-连锁隐性遗传视网膜色素变性家系的RPGR基因新突变

目的 研究X-连锁隐性遗传视网膜色素变性(RP)家系RPGR基因突变男性患者和女性携带者的临床表型.方法 家系调查研究.收集RP先证者及其家系资料,完善眼科检查,抽取现存77名家系成员和80名正常对照者外周静脉血,提取DNA,进行聚合酶链反应(PCR),扩增RPGR基因外显子ORF15,扩增产物纯化后直接测序.结果 RP家系中,8例RP患者均为男性,呈隔代传递,不存在男性至男性的传递,患者的母亲及女儿都是致病基因携带者而不发病,符合X-连锁隐性遗传方式.在8例男性RP患者和14例女性致病基因携带者的RPGR基因外显子ORF15+577_578位点发现一个AG缺失突变,引起阅读框架的改变,该基因缺失突变在家系中共分离.AG缺失突变导致男性患者典型的RP改变,但发病时间和进展程度不一.携带有杂合型基因突变的14例女性携带者最具特征性的临床表型是中高度近视眼(-5.00～-22.00 D).结论 该RP家系患者由RPGR 基因外显子ORF15移码突变致g.ORF15+577_578delAG位点缺失.RPGR基因外显子ORF15的新突变可导致男性患者严重的RP表型,但女性致病基因携带者仅表现为中高度近视眼.(中华眼科杂志,2011,47:516-520)

Abstract：

Objective To screen the mutation in the RPGR gene in a large Chinese family with X-linked recessive retinitis pigmentosa (RP) and to describe the phenotype in affected males and female carriers. Methods Ophthalmic examinations were performed in 77 family members of a RP pedigree to identify affected individuals. Polymerase chain reaction (PCR) and direct sequencing were used for screening of mutations in RPGR gene exon ORF15. Results Mutation screening demonstrated a novel mutation, g.ORF15+577_ 578delAG, which caused an open reading frameshift and resulted in premature truncation of the RPGR protein. This mutation was detected in 8 affected male individuals and 14 obligate female carriers in this family and was found to segregate with the phenotype in this family. This mutation led to a severe RP phenotype in male affected individuals with some variability in the age of onset of night blindness and loss of visual acuity, but was recessive in female carriers without a RP phenotype. However the most striking phenotypic feature in female carriers in this pedigree was moderate to high myopia with refractive error ranging from -5.00 D to -22.00 D in 14 female carriers. Conclusions This novel mutation in RPGR ORF15 causes serious RP phenotype in males and no RP phenotype in female carriers. Moderate to high myopia was a particular feature for female carriers in this pedigree. Our finding expands the spectrum of RPGR mutations causing RP and phenotypic spectrum of the disease in Chinese family, which is useful for further genetic consultation and genetic diagnosis.     

报告两个不同遗传方式成骨不全症回族家系

报告二个成骨不全症回族家系。家系调查和系谱分析表明,一个家系连续三代都有发病的,26人中共有11人罹患本症,为常染色体显性遗传;另一个家系先证者的父母为姨表兄妹近亲联姻,家系中连续4代(包括先证者的7岁姐姐在内)无一人见有本症,考虑为常染色体隐性遗传。     

一个常染色体显性遗传多囊肾疾病家系

目的通过一个家系分析,探讨常染色体显性遗传性多囊肾疾病的病因学、病理学、遗传学因素。方法通过对一多囊肾疾病家系4代34例家庭成员进行了调查,并对7例患者进行体检、超声、外周血染色体等检查。结果患者主要表现为单侧肾脏囊肿性疾病,40岁以后发病,伴有腹胀、腹痛、高血压、血尿等症状。家系遗传分析表明,该家系疾病属于常染色体显性遗传性多囊肾疾病。结论基因缺陷为本病的重要发病机制之一,本家系中如果任一亲代发病,子代中必有子女发病,并且从Ⅱ1所生3女1子全部发病,发病年龄均在40岁以后,其第4代有很高的发病风险。     

人类错配修复基因在HNPCC家系中的突变研究

目的 了解２９个遗传性非息肉病性结直肠癌（ＨＮＰＣＣ０这 中ｈＭＬＨＩ和ｈＭＳＨ２基因的种系突变状况。方法 ＨＰＣＲ－ＳＳＣＰ和ＤＮＡ测序的方法进行突变筛选。结果 （１）在２９个家系中,ｈＭＬＨ１和ｈＭＳＨ２两个基因的总突变率为３１．０％,与对照组（２％）相比差异有极显著性,其中ＨＭＬＨ１基因是主要的相关基因。（２）１０名患大肠癌的家系成员均含有与先证者相同的突变,反映了突变与在肠癌的主要的相关基     

亲缘群体单体型推断的研究进展

随着高通量的基因分型技术的出现,越来越多的单核苷酸多态性( single nucleotide polymorphism,SNP)可被检测。基因组研究中,单体型分析已被运用到SNP位点与复杂性状的关联分析中。现有的单体型推断方法包括基于非亲缘群体的方法,DNA pool样本方法和系谱资料方法。不过家庭及亲缘数据可为单体型推断提供很重要的信息,利用这些信息进行单体型推断会增加准确性。如今对亲缘群体单体型推断的算法和软件已有很多报道。该文的目的是回顾这些算法、软件以及它们的优缺点和适用的群体类型,同时探讨仍然存在的问题和面临的挑战。     

Analysis of the genotype and phenotye in 3 pedigrees with Stargardt disease北大核心CSCD

Objective: To analyze the relationship between genotype and phenotype in 3 pedigrees with Stargardt disease. Methods: Three pedigrees with Stargardt disease were included in Ningxia Eye Hospital from January 2017 to September 2017.The clinical features of patients and other family members were evaluated by ophthalmic examinations, including visual acuity, best corrected visual acuity (BCVA), fundus examination, optical coherence tomography (OCT), fundus fluorescein angiography (FFA) and electroretinogram (ERG). The periphery blood sample of 5 ml from patients and 1 family member with normal phonotye in each family were collected. The next generation sequencing, PCR and direct sequencing were used to confirm the disease-causing mutation. The relationship between genotype and phenotype was analyzed. This study was approved by Ethic Committee of Ningxia Eye Hospital and informed consent was obtained from each subject. Results: In 3 Stargardt pedigrees, 2 pedigrees showed autosomal recessive inheritance, and 1 pedigree was pseudodominant inheritance. Five mutations on ABCA4 gene were detected and p. F2188S and p. Y345C were novel muations. All pedigrees carried two heterozygous mutation. The onset age of the patients were adolescence except just one patient who suffered at the age of 50 years old. The visual acuity was severely affected and the OCT indicated different degrees of macular atrophy. The results of the ocular fundus photography and the FFA were variable. Conclusions: The patients with stargardt disease often carry heterozygous mutation on ABCA4 gene and available characteristics, including early onset age, varying ocular fundus and severe visual impairment. Next generation sequencing technique shows the advantages of rapid and high efficiency in the diagnosis of Stargardt disease. Copyright © 2018 by the Chinese Medical Association.