17q12染色体微缺失综合征产前诊断分析

目的:通过分析17q12染色体微缺失综合征的临床资料,探讨该综合征的胎儿期临床表型谱和产前诊断方法,为17q12染色体微缺失综合征患者及携带者的遗传学咨询及产前诊断提供依据。方法:选取2018年1月至2019年6月因超声检查发现胎儿肾脏皮质回声增强就诊于河南省人民医院产前诊断中心的患者。经羊水取样,并行染色体微阵列分析(CMA)。结果:CMA检测共发现胎儿17 q12微缺失综合征者5例,缺失片段1.18～1.52Mb,缺失区域与肾囊肿和糖尿病综合征致病区域部分重叠(chr17:34815072-36215917)。结论:对于超声检测出肾脏异常的胎儿,无论其是否合并其它畸形,均应行染色体核型和CMA检查,以及时确诊17q12染色体微缺失综合征胎儿,为胎儿出生后临床表现提供理论支持,为孕妇及家庭提供更为精准的遗传咨询。     

7p部分三体综合征的表型和基因型关系研究

目的:探讨7p部分三体综合征的起源,分析患者表型和基因型的关联性,同时研究单核苷酸多态-微阵列比较基因组杂交技术(SNP aCGH)在检测亚细胞遗传学改变中的应用价值。方法:对外院核型报告正常的1例特殊面容、低智合并先心患儿复查染色体,G带发现其4q35.2区域疑似有额外片断附着,进一步用SNP aCGH进行全基因组扫描,并用4号染色体长臂末端和7号染色体短臂末端探针与患儿淋巴细胞杂交(FISH)以验证SNP aCGH结果,同时对患儿进行家系调查及部分成员染色体检查。结果:患儿核型46,XX,add(4)(q35.2)?全基因组扫描显示,患儿7p21.1-pter区域有20.78Mb的重复,而4q35.2-qter区域有3.24Mb的缺失。FISH发现,患儿外周血淋巴细胞含3个拷贝的7号染色体短臂末端和1个拷贝的4号染色体长臂末端。家系调查发现,患儿父亲及祖父均为46,XY,t(4;7)(q35.2;p21.1)。综合以上结果,确定患儿核型为46,XX,der(4)t(4;7)(q35.2;p21.1)pat,异常核型由父亲传递,系精子在减数分裂中通过邻近分离-I所形成的不平衡产物。患儿不平衡片断包含与颅骨发育异常相关的TWIST基因、与先心相关的MOX2基因以及与颅面部异常特征相关的ACTB基因。结论:亲代平衡易位导致的子代小片断不平衡是7p部分三体综合征等出生缺陷的重要原因;SNP aCGH是鉴别小片断不平衡的有效手段;7p部分三体综合征患者异常表型可能与TWIST、MOX2、ACTB等基因有关。     

应用CMA诊断14q32微缺失综合征

目的 探讨14q32微缺失综合征的临床表现,进一步提高对该疾病的认识及对该疾病的产前及遗传学诊断.方法 对1例因"出生后口吐白沫伴气促1天"入院的胎儿进行遗传学诊断,结合常规染色体G显带分析及单核苷酸多态性微阵列(single nucleotide polymorphism array,SNP-array)技术进行分子...     

22q11.2微缺失综合征7例相关临床表型及病因分析

目的　探讨22q11.2微缺失综合征患儿的不同临床表现。方法　收集2006年7月至2007年6月在英国Oxford 儿童医院临床所见的7例经分子细胞遗传学分析（FISH检测）确诊为22q11.2微缺失综合征患儿的临床资料,分析其临床表现、诊断及治疗情况。结果　7例中男2例,女5例。7例均通过FISH检测确诊,1例为产前诊断,余6例的平均确诊年龄为2个月。2例（28.4%）为父母遗传致病,5例（71.6%）为基因突变致病。其中,先天性心脏病和面容异常的发生率均为100%,免疫功能异常28. 6%,颚裂14.3%,低钙14.3%。根据患儿的不同临床表现进行对症治疗。结论　22q11.2微缺失综合征患儿以心脏畸形及面容异常为突出表现,结合FISH检测可早期诊断,基因突变是其主要病因,以流出道受损为主的心脏畸形及以T淋巴细胞数量减少为主的免疫功能异常是影响预后的关键因素。     

6例有Pierre Robin序列征表型的新生儿全基因组拷贝数变异分析

目的 应用全基因组微阵列芯片平台,对6例具有Pierre Robin序列征(Pierre Robin sequence,PRS)表型的新生儿进行全基因组拷贝数变异(copy number variations,CNVs)检测,以发现与PRS相关的准确定位. 方法 对2009年6月至2010年5月复旦大学附属儿科医院新生儿病房收治的符合PRS表现的6例患儿进行研究.采用Cytogenetic Whole Genome芯片筛查全基因组CNVs,对发现的所有CNVs进行分析,参照国际基因组拷贝数变异多态性数据库除外正常人群多态性CNVs.结合已知PRS的相关区段进行分析,并与已发表文献进行比较. 结果 (1)6例患儿均具小下颌畸形、腭裂及舌后坠3种表型.此外,2例有其他特殊面容表现,2例有先天性心脏病,1例有先天性喉软骨发育不良,1例存在脉络膜多发囊性占位.(2)6例PRS患儿经微阵列芯片检测,最终获得7个罕见、有潜在临床意义的CNVs,分别为位于lp36.23-p26.22、l4q11.l-q11.2和20p13的重复,以及4q23、1 q43-q44的缺失各1例和l4q32.31的缺失2例.(3)文献比对分析显示,1q43-q44、14q32.31区段可能与PRS表型有关,1q43-q44区段包含与神经系统发育相关的基因AK T3和不均-核蛋白U(heterogeneous nuclear ribonucleoprotein U,hnRNPU);14q32区段编码核仁小分子RNA,可能为基因组印迹区. 结论 本研究提供了应用全基因组微阵列平台分析罕见、有潜在致病可能的CNVs方法,提示1q43-q44和14q32.31可能为与PRS有关的染色体区段.     

卵巢癌紫杉醇耐药细胞株OC_3/PIX_3及OC_3/PIX_5的比较基因组杂交研究

目的:了解两种卵巢癌紫杉醇耐药株(OC3/PIX3及OC3/PIX5)和其亲代细胞紫杉醇敏感株(OC3)染色体DNA拷贝数的差异变化,探讨耐药细胞的分子遗传学改变。方法:运用比较基因组杂交(comparative genom ic hybrid ization,CGH)技术,将OC3/PIX3及OC3/PIX5与其亲代细胞株OC3的染色体基因组进行比较分析。结果:3种细胞株的染色体2pter-p21、3q、5p、9均有遗传物质表达增加;10号染色体表达增加仅见于OC3。染色体1,4,6的遗传物质在3种细胞株的表达均有减少。3p的减少发生在OC3和OC3/PIX5。仅在OC3细胞中见到7q、8p减少。OC3和OC3/PIX5出现染色体10q22过度扩增。最有意义的变化是OC3/PIX3细胞染色体2p22的过度扩增。结论:2p22拷贝数过度扩增可能与卵巢癌紫杉醇耐药相关。     

胎儿心脏发育异常的染色体芯片检测及脐血心肌肌钙蛋白T(cTnT)水平研究

目的:1探讨胎儿心脏发育异常与遗传学异常的相关性。2探讨孕中期脐血心肌肌钙蛋白T(cardiac troponin T,cTnT)水平预警心脏发育异常胎儿心肌损伤的可能性。方法:选择40例孕中期心脏超声提示胎儿心脏发育异常的胎儿作为研究组,另选择同期26例无心脏发育异常胎儿作为对照组。所有妊娠均为单胎妊娠。分别采集胎儿的脐静脉血,一部分血样行染色体核型分析及染色体拷贝数微阵列芯片(micro-array)分析;另一部分血样测定脐血血浆c Tn T水平。结果:1脐血染色体分析:对照组26例胎儿样本核型均正常;研究组40例中有4例染色体异常,其中21-三体2例,69,XXX 1例,46,XX,-4,+der(4)(?::p14-qter)1例;4例为染色体多态性改变,分别涉及1号、9号、13号染色体的可变区域。2研究组芯片检测共检出3例致病性拷贝数变异,22号染色体微缺失导致的腭心面综合征1例:arr 22q11.21(18,919,942-21,440,514)X1;4号染色体短臂末端大片段缺失1例:arr 4p25.3-p16.3(71,552-16,833,303)X3;10号染色体长臂末端片段缺失1例:arr10q15.3(130,650,432-135,404,523)X1。3研究组中遗传学检测异常发生率为15%(6/40)。研究组脐血cTnT水平较对照组增高(488.572±73.528 ng/L vs 315.841±85.665 ng/L),差异有统计学意义(P0.01)。结论:1心脏发育异常胎儿合并遗传学异常几率增加。2心脏结构异常胎儿脐血cTnT水平显著增加,提示心肌组织在异常发育的胎儿心脏结构重塑过程中可能发生损伤,脐血cTnT可作为潜在早期预警胎儿心脏功能异常的生物化学标志物。     

染色体微阵列分析技术在复发性自然流产遗传学诊断中的应用

目的:探讨染色体微阵列分析(CMA)在复发性自然流产(RM)遗传学诊断中的应用价值,研究既往流产次数与胚胎染色体异常率的关系以及致病性微缺失/微重复与RM的相关性。方法:选取2011年8月至2021年9月在南京医科大学附属妇产医院就诊的1355例RM病例,取流产绒毛行CMA检测。结果:排除14例(1.0%,14/1355)重度母体细胞污染样本,共1341例病例纳入研究。1341例RM病例中,共检出致病性染色体异常813例(60.6%),其中异倍体597例(44.5%)、多倍体113例(8.4%)、大片段结构异常67例(5.0%)、致病性微缺失/微重复25例(1.9%)、单亲二体(UPD)11例(0.8%)。孕妇流产2次、3次和≥4次组病例的染色体异常率分别为62.6%、56.5%和51.9%,流产2次组病例的染色体异常率显著高于流产3次、≥4次组(P<0.05)。本研究发现5个可能与RM发生相关的复发性(n≥2)致病性微缺失/微重复(15q11.2、19p13.3、22q13.2q13.33微缺失和17p13.3、22q11.1q11.21微重复),其中22q13.2q13.33...     

39例生长受限胎儿染色体微阵列芯片分析

目的:探讨染色体微阵列分析技术(CMA)在胎儿生长受限(FGR)产前诊断中的应用价值。方法:对39例核型分析正常的FGR样本进行CMA检测,分析CMA异常的检出率。结果:39例FGR中CMA检出5例异常,检出率12.8%(5/39)。22例特发性FGR中检出4例异常,检出率18.2%(4/22),包括1例4q21.21微缺失,1例2q11.1q11.2微重复及2例7q11.23微缺失。17例FGR合并其他超声异常中检出1例异常,检出率5.9%(1/17),1例异常为4p16.3p16.2微重复。结论:对FGR行CMA检测有助于发现核型分析无法检出的染色体亚显微结构异常。CMA有利于提高对FGR遗传病因的诊断。     

应用荧光原位杂交技术诊断复杂的染色体重排1例

复杂的染色体重排(CCR)足一种罕见的细胞遗传学异常,涉及到3个或更多的染色体重排,包括染色体的缺失,插入或倒位。目前,应用常规细胞遗传学及显带技术还很难对其进行准确地诊断。 患者G5P1,曾分别于12、14、20孕周发生自然流产,亦分娩过1健康男婴。流产组织(20孕周)的细胞遗传学分析显示出异常胎儿核型:46,XX,-5,-7,+der(5)t(5;7)(p15;q31),+der(7)t(7;11)(q31;q13)。此次妊娠第16周始接受产前检查,被确诊为涉及到5、7、11号染色体的CCR携带者,而其     

Prenatal diagnosis of Cri-du-Chat syndrome with concomitant distal trisomy 10q syndrome in one fetus with ultrasound anomalies

ObjectiveThe aim of this work was to characterize the genetic abnormalities and prenatal diagnosis indications in one fetus with Cri-du-Chat syndrome with codependent 10q24.2-q26.3 duplication in prenatal screening.Materials and methodsA 31-year-old woman had a second trimester serum screening that indicated the fetus was at low risk. During this pregnancy, the woman underwent amniocentesis at 18⁺⁴ weeks' gestation because of adverse fertility history and nuchal fold thickening. Cytogenetic analysis and next-generation sequencing analysis were simultaneously performed to provide genetic analysis of fetal amniotic fluid. According to abnormal results, parental chromosome karyotype of peripheral blood was performed to analysis.ResultsCNV-seq detected a 14.00 Mb deletion at 5p15.33-p15.2 and a 34.06 Mb duplication at 10q24.2-q26.3 in the fetus. Cytogenetic analysis of the fetus revealed a karyotype of 46, XY, der(5) t(5;10) (p15.2;q26.3). The karyotype of pregnant women was 46,XX,t(5;10) (p15.2;q24.2). The pregnancy was subsequently terminated after sufficient informed consent.ConclusionThis is the first study that reports prenatal diagnosis of a Cri-du-Chat syndrome with concomitant 10 q24.2-q26.3 duplication. Adverse pregnancy history has to be as an important indicator for prenatal diagnosis, and the genetic factors of abnormal pregnancy should be identified before next pregnancy. Nuchal fold thickening is closely related to fetal abnormalities. Combined with ultrasonography, the use of CNV-seq will improve the diagnosis of submicroscopic chromosomal aberrations in fetuses with congenital anomalies.     

Prenatal diagnosis of a fetus with unbalanced translocation (4;13)(p16;q32) with overlapping features of Patau and Wolf-Hirschhorn syndromes

Wolf-Hirschhorn syndrome (WHS) and Patau syndrome are two of the most severe conditions resulting from chromosome abnormalities. WHS is caused by a deletion of 4p16, while Patau syndrome is caused by trisomy for some or all regions of chromosome 13. Though the etiologies of these syndromes differ, they share several features including pre- and postnatal growth retardation, microcephaly, cleft lip and palate, and cardiac anomalies. We present here a female fetus with deletion of 4p16 --> pter and duplication of 13q32 --> qter due to unbalanced segregation of t(4;13)(p16;q32) in the father. She displayed overlapping features of both of these syndromes on ultrasound. To the best of our knowledge, this is the first report of a fetus with both partial trisomy 13 and deletion of 4p16, the critical region for WHS.     

Prenatal diagnosis of partial monosomy 18p(18p11.2-->pter) and trisomy 21q(21q22.3-->qter) with alobar holoprosencephaly and premaxillary agenesis

A prenatal diagnosis of partial monosomy 18p(18p11.2-->pter) and trisomy 21q(21q22.3-->qter) in a fetus with alobar holoprosencephaly (HPE) and premaxillary agenesis (PMA) but without the classical Down syndrome phenotype is reported. A 27-year-old primigravida woman was referred for genetic counselling at 21 weeks' gestation due to sonographic findings of craniofacial abnormalities. Level II ultrasonograms manifested alobar HPE and median orofacial cleft. Cytogenetic analysis and fluorescence in situ hybridization (FISH) on cells obtained from amniocentesis revealed partial monosomy 18p and a cryptic duplication of 21q,46,XY,der(18)t(18;21)(p11.2;q22.3), resulting from a maternal t(18;21) reciprocal translocation. The breakpoints were ascertained by molecular genetic analysis. The pregnancy was terminated. Autopsy showed alobar HPE with PMA, pituitary dysplasia, clinodactyly and classical 18p deletion phenotype but without the presence of major typical phenotypic features of Down syndrome. The phenotype of this antenatally diagnosed case is compared with those observed in six previously reported cases with monosomy 18p due to 18;21 translocation. The present study is the first report of concomitant deletion of HPE critical region of chromosome 18p11.3 and cryptic duplication of a small segment of distal chromosome 21q22.3 outside Down syndrome critical region. The present study shows that cytogenetic analyses are important in detecting chromosomal aberrations in pregnancies with prenatally detected craniofacial abnormalities, and adjunctive molecular investigations are useful in elucidating the genetic pathogenesis of dysmorphism.     

Prenatal detection of a de novo terminal inverted duplication 4p in a fetus with the Wolf-Hirschhorn syndrome phenotype

OBJECTIVES: To present the prenatal diagnosis of a de novo terminal inversion duplication of the short arm of chromosome 4 and a review of the literature. CASE: An amniocentesis for chromosome analysis was performed at 33 weeks' gestation because ultrasound examination showed a female fetus with multiple abnormalities consisting of severe intrauterine growth retardation, microcephaly, a cleft lip and renal hypoplasia. RESULTS: Cytogenetic analysis and FISH studies of the cultured amniocytes revealed a de novo terminal inversion duplication of the short arm of chromosome 4 characterized by a duplication of 4p14-p16.1 chromosome region concomitant with a terminal deletion 4p16.1-pter. The karyotype was thus: 46,XX, inv dup del (4)(:p14-->p16.1::p16.1-->qter). The parents opted to terminate the pregnancy. Fetopathological examination showed dysmorphic features and abnormalities consistent with a Wolf-Hirschhorn syndrome (WHS) diagnosis, clinical manifestations of partial 4p trisomy being mild. CONCLUSION: Although relatively rare, inverted duplications have been reported repeatedly in an increasing number of chromosomes. Only two previous cases with de novo inv dup del (4p) and one with tandem dup 4p have been reported, all of them associated with a 4pter deletion. We report the first case diagnosed prenatally. Breakpoints are variable, resulting in different abnormal phenotype. In our case, clinical manifestations resulted in a WHS phenotype.     

Genetic heterogeneity and phenotypic anomalies in children with atrioventricular canal defect and tetralogy of Fallot

Tetralogy of Fallot associated with the atrioventricular canal defect has been usually reported in association with Down syndrome. The aim of the present study was to describe the cardiac aspects and the genetic anomalies in children with this association of heart defects. We identified 64 patients with atrioventricular canal defect tetralogy of Fallot. All children underwent complete cardiovascular, clinical phenotypic and genetic evaluation. A genetic syndrome or extracardiac anomalies were found in 56 patients (87.5%). Down syndrome (43 patients, 67.2%) was the most frequent genetic diagnosis. Other syndromes were 8p deletion, trisomy 13, duplication 5p, cranio-cerebello-cardiac syndrome, Cantrell syndrome, CHARGE association, VACTERL association, and DiGeorge syndrome related to maternal diabetes. No patients in our series had 22q11 deletion. Tetralogy of Fallot with extreme dextroposition of the aorta was found in seven patients (only one with Down syndrome). Additional cardiac malformations were present in 23 patients (only 11 with Down syndrome). The association between atrioventricular canal defect and tetralogy of Fallot represents a cardiac phenotype with strong genetic characteristics. For this reason, a careful genetic examination is required. Our study confirms the high prevalence of Down syndrome, but also reveals a significant genetic heterogeneity. Additional cardiac defects are prevalent in patients without Down syndrome.     

A patient with a de novo t (6;9) and an interstitial duplication of (9)(q21.2q22.1).

We report on a 4-year-old child with psychomotor retardation, general hypotonia and only mild dysmorphic features. Her chromosome constitution was 46,XX, t (6;9) (q27;q22.1), dup (9) (q21.2q22.1). This de novo interstitial duplication was confirmed using fluorescence in situ hybridisation (FISH) with band-specific probes. This is the second report of a patient with an interstitial duplication of this region of the long arm of chromosome 9. It is concluded that in a child with an abnormal phenotype and a de novo (apparently) balanced translocation, the possibility of a small duplication or deletion should be considered.     

Six cases of deletion 9p24 and trisomy 19q13.4 inherited from a familial balanced translocation.

The deletion 9p with trisomy 19q syndrome is a rare disorder. We report 2 adults and 4 children with deletion 9p and trisomy 19q due to familial balanced 9p;19q translocation with clinical features suggestive of monosomy 9p. The children had dysmorphic features and psychomotor retardation while the adults were self-sufficient but worked in a sheltered environment. High-resolution chromosome analysis and fluorescence in situ hybridization confirmed that the 6 cases of unbalanced translocation, der(9)t(9;19)(p24.1;q13.4) were inherited from a balanced translocation carrier, t(9;19)(p24.1;q13.4). The dysmorphic features included trigonocephaly, small nose with stunted tip, and long philtrum. Associated anomalies included wide-set nipples, extra finger flexion creases, hernia, external genitalia hypoplasia, scoliosis, and hypopigmented skin patch. We suggest that genetic counseling is necessary for those who have family members with dysmorphic features and/or major anomalies and/or psychomotor retardation.     

Application of array comparative genomic hybridization (aCGH) for identification of chromosomal aberrations in the recurrent pregnancy loss

Spontaneous abortion occurs in 8–20% of recognized pregnancies and usually takes place in the first trimester (7–11 weeks). There are many causes of pregnancy loss, but the most important (about 75%) is the presence of chromosomal aberrations. We present the results of oligonucleotide array application in a cohort of 62 miscarriage cases. The inclusion criteria for the study were the loss after 8th week of pregnancy and the appearance of recurrent miscarriages. DNA was extracted from trophoblast or fetal skin fibroblasts. In the 62 tested materials from recurrent miscarriages, the detection rate was 56.5% (35/62). The most commonly found were aneuploidies (65%) (chromosomal trisomy 14, 16, 18, 21, and 22), Turner syndrome, and triploidy (17.1%). Other chromosomal abnormalities included pathogenic and likely pathogenic structural aberrations: 1) pathogenic: deletion 7p22.3p12.3 and duplication 9p24.3p13.2 inherited from the normal father, deletion 3q13.31q22.2 and deletion 3q22.3q23 of unknown inheritance and duplication of 17p12 inherited from father with foot malformation; 2) likely pathogenic variants: deletion 17p13.1 inherited from normal mother, deletion 5q14.3 of unknown inheritance and de novo deletion 1q21.1q21.2. Among these aberrations, six CNVs (copy number variants) were responsible for the miscarriage: deletion 7p22.3p12.3 and duplication 9p24.3p13.2, deletion 3q13.31q22.2 and deletion 3q22.3q23, and deletion 17p13.1 and deletion 1q21.1q21.2. Other two findings were classified as incidental findings (deletion 5q14.3 and 17p12 duplication). Our research shows that 17% of the aberrations (6/35 abnormal results) that cannot be identified by the routine kariotype analysis are structural aberrations containing genes important for fetal development, the mutations of which may cause spontaneous abortion.     

女性表型46,XY性发育障碍的临床、病理特征及遗传学检测

目的:总结女性表型的46,XY性发育障碍患者的临床及病理学特点,对其进行鉴别诊断及遗传学检测,为类似病例的诊断和鉴别诊断提供借鉴资料。方法:回顾分析2010年至2015年在深圳市妇幼保健院行妇科手术的3例46,XY性发育障碍患者的临床资料。将切除的性腺组织进行病理学诊断;提取患者及家属基因组DNA,应用Sanger测序、二代测序方法、MLPA、染色体基因组芯片分析等方法进行遗传学检测以寻找致病基因变异。结果:1例患者为完全型雄激素不敏感综合征(CAIS),病理结果证实一侧隐睾见精原细胞瘤,其AR基因第7外显子检测到移码突变c.2546_2547 insA(p.N849K,fs X32),此突变为已报道导致CAIS的突变方式;1例患者临床诊断为单纯性腺发育不良,性腺病理结果为不成熟的卵巢组织,患者SRY基因的HMG区域检测到c.206TC(p.V69A)突变,此突变未见报道;1例患者临床诊断为单纯性腺发育不良,病理结果为双侧性腺母细胞瘤伴无性细胞瘤,性发育相关基因未检测到明确的致病突变。结论:综合利用多种检测方法对女性表型46,XY性发育障碍患者进行致病基因检测,其中2例患者分别由AR基因、SRY基因突变引起,其中SRY基因c.206TC(p.V69A)为新发现的突变。