正常与异常的色觉基因

人类具有三种色觉基因。“蓝色”基因位于7号染色体上,而“红色”与“绿色”基因位于X染色体长臂末端-Xq28。相应的色素位于三种不同类型的视锥细胞中。这些色素具有特征性的最大吸收光谱:蓝色为短波,长420nm;绿色为中波,长530nm;红色为长波,长560nm。“绿色”与“红色”的设计是最简便的,因为这两种色素可把吸收光谱调节到包括整个可见光谱。与视紫质有关的一个基因位于3号染色体上,且只在视椎细胞中表达,产生无色暗视觉(495nm)。累及绿色和红色色素基因的X连锁色盲     

单纯性生长激素缺乏症IA型患者GH1基因缺失位点的研究

单纯性生长激素缺乏症（ＩＧＨＤⅠＡ型）的分子基础是生长激素结构基因（ＧＨ１）的缺失。为了进一步明确ＧＨ１基因缺失的发生机理，应用ＰＣＲ方法钓出了２名患者的包括缺失位点在内的基因片段，克隆后用双脱氧法进行序列分析。结果发现：２例患者在ＧＨ基因簇１８３３～２４２９ｂｐ、８４４６～９０４２ｂｐ位点的两段５９６ｂｐ（９９％同源）基因片段间发生了３次基因的同源性重组交换，从而导致了包括ＧＨ１基因在内的６．７ｋｂ的基因片段缺失。为研究同源重组的分子机理提供了依据。     

散发性肾癌中VHL基因的两个单核苷酸多态位点分析和杂合性缺失检测

目的检测79例散发性肾癌中抑癌基因VHL内部的两个单核苷酶多态(single nucleotide polymorphism，SNP)位点并分析杂合性缺失(loss of heterozygosity，LOH)发生情况，探讨VHL基因LOH与肾癌临床病理特征的关系。方法从肿瘤和正常肾组织中提取DNA，应用聚合酶链反应-限制性片段长度多态性方法检测VHL基因5′端SNP位点rs779805和3′端SNP位点rs1642742的基因型。在两个位点的杂合子中进行LOH检测，并分析VHL基因LOH与临床病理特征的关系。结果我们计算了两个位点的基因型、基因频率、杂合度、多态信息含量等遗传学参数。综合两个位点发现杂合子29例．其中12例(41．4％)存在LOH。VHL基因LOH与肾癌发生年龄、性别、临床分期、病理分级无显著相关性。结论在散发性肾癌中，VHL基因LOH是肿瘤发生的重要机理，其发生率达41．4％，VHL基因LOH与肾癌分期、分级无关。     

一个 FBN2基因新剪接位点变异致先天性挛缩蜘蛛指畸形的遗传学分析

目的:对1例疑似先天性挛缩蜘蛛指畸形患者进行变异筛查,探讨其可能的分子遗传学发病机制,为临床诊断提供依据。方法:应用全外显子测序技术筛查基因变异。候选致病基因剪接位点变异经Sanger测序验证后,经RT-PCR、TA克隆测序确定新转录本序列。结果:患者 FBN2基因存在c.533-1G>C杂合变异,未见报道...     

乳腺癌中p53基因缺失及p53蛋白的异常表达

乳腺癌中ｐ５３基因缺失及ｐ５３蛋白的异常表达郭文斌张嘉庆杨德启乔新民张庆广阚秀虞有智一、材料与方法１．材料来源：４７例乳腺癌及正常腺体均来自我院乳腺中心１９９４～１９９６年间手术切除标本。全部病例均有病理学诊断。２．Ｓｏｕｔｈｅｒｎ杂交：用酚、氯仿／...     

COL1A1基因PCOL2和Sp1结合位点多态与先天性髋脱位的关联分析

目的 研究Ⅰ型胶原a1链(collagen type Ⅰ alpha 1，COL1A1)基因PCOL2和Sp1结合位点多态性在中国北方人群中的分布，并探讨其与先天性髋脱位(congenital dislocation of the hip，CDH)的关系。方法 在81个CDH核心家系的243名成员中，采用聚合酶链反应-限制性片段长度多态性分析方法，对位于COLIAI基因启动子内的PCOL2多态(-1997G／T)和转录调控区第1内含子内的Sp1多态(1546G／T)进行基因分型，并进行传递不平衡检验。结果COL1A1，基因PCOL2结合位点G／T多态与CDH不存在明显关联(P=0．537)，中国人PCOL2多态位点的基因型和等位基因频率分布与西班牙白人群和美国白人群差异存在统计学意义；Sp1结合位点只检测到SS基因型，未检测到Ss或ss基因型。结论 COL1A1基因PCOL2和Sp1结合位点多态存在种族差异，PCOL2和Sp1结合位点多态可能与中国人CDH的发病风险无关。     

小儿先天性心脏病与染色体异常的关系

先天性心脏病（congenital heart disease,CHD）是目前最常见的先天性畸形,也是引起婴幼儿死亡的首要原因。先心病是一种多基因遗传病,主要由于胚胎期遗传因素和环境因素共同作用导致心脏血管异常发育所引起,遗传度为55％-65％。先心病不但涉及多种基因,且与这些基因在不同时间和不同空间的先后表达和相互作用有关,其中任何基因表达质或量的异常,都可能影响心脏的发育,导致先心病的发生。     

男性性发育异常患者的SRY基因缺失和SOX9基因的第一外显子部分缺失分析

目的探讨SRY和SOX9基因在性发育异常基因诊断中的意义。方法染色体核型分析结合PCR扩增SRY基因和SOX9基因第一外显子。结果两病例染色体检查结果均为46,XY,未发现异常;病例1 SRY基因缺失,SOX9基因第一外显子未见异常;病例2 SRY基因未见异常,SOX9基因第一外显子部分缺失。结论 SRY基因缺失是导致病例1发病的原因,SOX9基因第一外显子部分缺失是导致病例2发病的原因。     

一个新的ACTC1基因5’端剪切位点突变可能在先天性心脏病室间隔缺损发病中起重要作用

背景：ACTC1是先天性心脏病的候选基因,且与人类先天性心脏病房间隔缺损有关。 目的：对110个先天性心脏病核心家系中ACTC1基因进行突变筛查。 方法：在110个先天性心脏病核心家系与300例无报道有心脏畸形的正常人之间进行对照试验。使用5对引物将ACTC1基因的6个编码区片段进行PCR体外扩增,从PCR产物中筛查基因突变。 结果与结论：在ACTC1基因的第五外显子下游5’端剪切位点第3个碱基发现了1个G-A的全新的突变。这个突变存在于1个患有单纯性室间隔缺损的女孩和她30岁的没有报道过心脏畸形的父亲,且该突变没有在300例正常对照组中筛出。提示该突变可能与人类先天性心脏病室间隔缺损有关。     

An insertion/deletion <Emphasis Type="Italic">TEX28</Emphasis> polymorphism and its application to analysis of red/green visual pigment gene arrays

TEX28 gene (fTEX) is present immediately downstream of the red/green visual pigment gene array on the human X chromosome. Its pseudogene (pTEX) that lacks exon 1 is present within the array between pigment genes. We found that both fTEX and pTEX genes had a 697 bp insertion/deletion polymorphism in their introns 3. In color-normal male subjects, the frequency of the 697 bp region was 43% (40/94) in pTEX and 97% (91/94) in fTEX in the array of Red-pTEX-Green-fTEX and 10% (9/94) in pTEX and 87% (41/47) in fTEX in the array of Red-pTEX-Green-pTEX-Green-fTEX. These results suggest that normal arrays with multiple green genes may have arisen through gene duplication rather than unequal homologous crossover. In color-vision-deficient male subjects with a single-gene array, the frequency of the 697 bp region was 83% (25/30) in the array of Green-fTEX and 66% (74/112) in the array of Red-fTEX. In color-vision-deficient male subjects with a 2-gene array, the frequency of the region was 44% (16/36) in pTEX and 97% (35/36) in fTEX in the array of Green-pTEX-Green-fTEX and 75% (18/24) in pTEX and 92% (22/24) in fTEX in the array of Red-pTEX-Red-fTEX. These results suggest that 2-green-gene arrays have arisen through unequal homologous crossover between a normal 2-gene array and a single-green-gene array. With data from a long-range PCR method using the insertion/deletion polymorphism, we proposed a structure of the second gene of 3-gene arrays, Green-pTEX-Green-pTEX-Green-fTEX and Red-pTEX-Red-pTEX-Red-fTEX, in color-vision-deficient subjects.     

胃癌中p16基因缺失与突变的研究

目的:调查胃癌患者p16基因的改变。方法:采用PCR和DNA测序方法,对36例胃癌患者肿瘤组织标本的p16基因外显子1、2和3进行检测,研究p16基因的缺失和突变情况。结果:发现2例有p16基因外显子1的纯合缺失,3例有外显子3的纯合缺失,缺失频率为13.89%,5例均为弥漫型胃癌。所有标本未检出点突变。结论:p16基因的缺失与胃癌的发生和发展有一定的联系。     

一个先天性肌营养不良症家系的POMT1基因突变鉴定与产前诊断CSCD

目的确定1个先天性肌营养不良症（congenital muscular dystrophy, CMD）家系的POMT1致病基因突变,并对该家系中孕11周的胎儿进行产前诊断。方法收集1例CMD患者及其表型正常父母的外周血标本,抽取母亲孕11周胎儿的绒毛标本。采用PCR扩增POMT1基因的第19和第20外显子,对PCR产物进行双向测序检测基因突变,明确致病突变来源后,进一步对胎儿进行产前诊断。结果先证者POMT1基因第19外显子检测到C．1939G〉A（P．Ala647Thr）杂合错义突变,来自其母亲;第20外显子检测到C．2141delG（P．Trp714Ter）杂合框移突变,导致蛋白质翻译的提前终止,该突变来自其父亲。产前诊断结果显示胎儿携带POMT1基因第19外显子c．1939G〉A杂合错义突变,推测其为与母亲相同POMn基因致病突变携带者的可能性大。结论POMT1基因第19外显子C．1939G〉A错义突变和第20外显子C．2141delG移码突变的复合杂合突变可能是该CMD家系的致病原因,符合常染色体隐性遗传的规律,通过基因产前诊断可以有效阻止致病突变的传递。     

WDR11 is another causative gene for coloboma,cardiac anomaly and growth retardation in 10q26 deletion syndrome

10q26 deletion syndrome is caused by a rare chromosomal abnormality, and patients with this syndrome present with an extensive and heterogeneous phenotypic spectrum. Several genes, such as EMX2 and FGFR2, were identified as the cause genital anomalies and facial dysmorphism in 10q26 deletion syndrome. However, the critical region for 10q26 deletion syndrome is not determined and the precise relationships between the causative genes and the phenotypes are still controversial.WD repeat domain 11 (WDR11), located at 10q25–26, was recently identified as a causative gene in hypogonadotropic hypogonadism, but other clinical phenotypes caused by WDR11 variants have not been identified. In this study, we have identified a WDR11 missense mutation, NM_018117.11: c.2108G > A; p.(Arg703Gln); ClinVar accession SCV000852064, in a two-year-old boy with severe growth retardation, ventricular septal defect, and coloboma symptoms. The case suggests that WDR11 is partially responsible for the clinical features of 10q26 deletion syndrome and provides novel insights into the pathophysiology of this syndrome.     

小鼠IL-12单链融合基因真核表达质粒构建及其肿瘤基因治疗初探

目的　构建小鼠IL 12单链融合基因 (msIL 12 ) ,进行基因治疗初探。方法　用RT PCR法从小鼠腹腔巨噬细胞总RNA分别获取p4 0cDNA和p35cDNA ,2次PCR引入linker后 ,依次克隆入pcDNA3质粒 ,构建成msIL 12真核表达质粒 (pmsIL 12 ) ;用DEAE dextran法将PEG纯化的pmsIL 12转染COS 7细胞 ,用ELISA法检测其培养上清 (转染上清 )IL 12蛋白含量。皮内注射PEG纯化的pmsIL 12 ,用MTT法检测其对正常小鼠脾细胞NK活性的影响 ,观察其对荷H2 2腹水型肝癌细胞瘤小鼠生存期的影响。结果　所得p35cDNA序列与GenBank登录号M86 6 72完全一致 ;所得IL 12p4 0cDNA序列与GenBank登录号AH0 0 4 85 9报道完全相同 ,除第 10 0 0位碱基是G而不是A(但所编码氨基酸相同 ,都是丝氨酸 )外也与GenBank登录号M86 6 71报道相同。成功构建了小鼠IL 12单链融合基因真核表达质粒pmsIL 12 ,其转染COS 7细胞后的转染上清IL 12蛋白含量达 (2 .5 5± 0 .6 0 )ng ml。皮内注射pmsIL 12后 ,使正常小鼠脾细胞NK活性显著增强 (P <0 .0 1) ,使荷H2 2肝癌细胞瘤小鼠的生存期明显延长(P <0 .0 5 )。结论　构建了小鼠IL 12单链融合基因的真核表达质粒 ,可用于基因治疗研究。     

5.78 Mb terminal deletion of chromosome 15q in a girl, evaluation of NR2F2 as candidate gene for congenital heart defects

All patients with terminal deletion of chromosome 15q have been reported to show intrauterine growth retardation, postnatal growth retardation, abnormal facial appearance and developmental delay. Haploinsufficiency of IGF1R was considered to be responsible for these symptoms. However, it is difficult to explain other symptoms seen in some of the patients, such as congenital heart defects by the absence of IGF1R alone. Here, we reported a patient with congenital heart defects and a 5.78 Mb terminal deletion of chromosome 15q detected by array-CGH. Among the patients reported to share congenital heart defects and terminal deletion of chromosome 15q, our patient had the smallest deletion. Evaluating the deletion map, NR2F2 was considered a candidate gene contributing to congenital heart defects in patients with terminal deletion of chromosome 15q.     

Mucopolysaccharidosis IVA: Submicroscopic deletion of 16q24.3 and a novel R386C mutation of n-acetylgalactosamine-6-sulfate sulfatase gene in a classical Morquio disease

The N-acetylgalactosamine-6-sulfate sulfatase (GALNS) gene, which is responsible for autosomal recessive mucopolysaccharidosis IVA (MPSIVA), has been assigned to the long arm of chromosome 16, subregion 24.3, an area where the adenine phosophoribosyltransferase (APRT) gene and renal dipeptidase (DPEP I) gene are also localized. Molecular genetic studies on a severely affected patient with MPSIVA (Morquio disease), without karyotypic abnormality, revealed a partial submicroscopic deletion of 16q24.3 and a single point mutation on the other allele, with no functional GALNS activity. The patient, his mother, and siblings were hemizygous for GALNS and APRT loci, evidenced by informative RFLP and gene dosage analyses combined with a fluorescence in situ hybridization, utilizing a partial genomic clone of GALNS, but heterozygosity was retained at the DPEP I locus and proximal D16S7. Haplotyping of the family members revealed recombinational events between DPEP I locus and three other polymorphic loci on the paternal chromosome, localizing GALNS gene on the proximal side to DPEP I gene. As estimated from the genetic distance between two flanking markers of proximal D16S7 and distal DPEP I locus, size of the deletion was less than 3Mb. Mother of the boy and two older siblings were asymptomatic, despite this interstitial deletion of the Giemsa-light G band. The remaining paternal allele had no gene rearrangement but GALNS activity was not encoded as Arginine at 386 was replaced with Cysteine (R386C), suggesting this alteration accounts for the severe phenotype. Allelic loss of APRT is frequently observed in cancer tissues, thereby suggesting that the tumor suppressor gene locates near the APRT locus. No family member has evidence of any malignant disease. This study is apparently the first documentation of interstitial deletion of 16q24.3, involving GALNS and APRT genes. © 1996 Wiley-Liss, Inc.