复发性流产夫妇的染色体结构异常分析

目的:探讨复发性流产与染色体结构异常的关系。方法:对有复发性自然流产史的112对夫妇进行外周血染色体核型分析。结果:112对夫妇中有20例染色体核型异常,异常检出率8.9％。其中平衡易位4例,复杂易位1例,臂间倒位8例,Y染色体变异6例,占2.7％;常染色体变异1例。结论:复发性流产夫妇任何一方的染色体结构异常均可引起流产等不良妊娠,9号染色体倒位和Y染色体变异与早期流产的关系密切。     

自然流产夫妇的细胞遗传学研究─附10例世界首报染色体核型

用人体外周血淋巴细胞培养法对６２４对原因不明的自然流产夫妇进行了细胞遗传学研究，检出异常染色体携带者５７例，其中女３８例，男１９例。５７例染色体异常中，结构异常４５例；染色体数目异常２例；９号染色体臂间倒位９例，Ｙ染色体倒位１例。异常染色体涉及到１，３，４，５，６，７，８，９，１０，１１，１３，１４，１５，１７，１８，１９，２１，２２，Ｘ，Ｙ共２０条。４５例结构异常中１０例经湖南医科大学国家细胞遗传学培训中心鉴定为世界首报。     

自然流产夫妇的细胞遗传学研究─附10例世界首报染色体核型

用人体外周血淋巴细胞培养法对６２４对原因不明的自然流产夫妇进行了细胞遗传学研究，检出异常染色体携带者５７例，其中女３８例，男１９例。５７例染色体异常中，结构异常４５例；染色体数目异常２例；９号染色体臂间倒位９例，Ｙ染色体倒位１例。异常染色体涉及到１，３，４，５，６，７，８，９，１０，１１，１３，１４，１５，１７，１８，１９，２１，２２，Ｘ，Ｙ共２０条。４５例结构异常中１０例经湖南医科大学国家细胞遗传学培训中心鉴定为世界首报。     

22例染色体平衡易位携带者优生遗传咨询

本文对我科自1982年8月至1991年12月间检出的22例平衡易位携带者进行分析,结果显示:此组病人以反复自然流产而就诊者最多,占77.27％;其次是曾分娩畸形儿死胎者,占9.09％。染色体核型分析以罗伯逊易位为最多,占81.82％,其中非同源染色体罗伯逊易位占77.78％,同源染色体罗伯逊易位占22.22％;染色体相互易位占18.18％。本文建议同源染色体罗伯逊易位者,应劝其绝育,非同源染色体平衡易位者,可于孕中期取羊水细胞培养进行产前诊断。     

习惯性流产夫妇外周血及绒毛染色体分析

本文分析了１１２例习惯性性流产夫妇外周血染色体及２９例（３８人次）习惯流产妇女再次妊娠流产时绒毛染色体检查结果。结果表明，４例（３．６％）习惯性流产夫妇一方有外周血染色体异常，异常类型均为平衡易位。３８人次绒毛染色体结果中１４例（３６．８％）染色体异常，其中７１．４％为常染色体三体或常染色体三体嵌合体。本结果表明对习惯性流产夫妇进行常规的外周血染色体检查及对流产胚胎进行绒毛染色体检查是十分必要的。     

平衡易位携带者孕中期产前诊断结果分析

目的:探讨平衡易位携带者孕中期胎儿产前诊断结果及妊娠结局,为平衡易位携带者遗传咨询及生育指导提供科学依据。方法:选择2015年1月至2016年12月夫妻之一为平衡易位携带者65例,于妊娠18~24周在我院行羊水染色体核型检查,并针对检测结果进行分析。结果:65例平衡易位携带者,28例(43.1%)胎儿染色体核型正常,25例(38.5%)胎儿为平衡易位携带者,12例(18.4%)胎儿为不平衡易位患者。其中总妊娠次数为187次,早期流产总次数为122次(65.2%);妊娠活产53次(28.3%),此次妊娠活产率81.5%(53/65);引产12次(6.4%)。13号与14号染色体发生相互易位的几率最高(16.2%,19.2%),其生育不平衡胎儿的几率分别为4.8%和12.0%。结论:平衡易位携带者夫妇其早期流产发生率较高,妊娠到孕中期后获得染色体正常后代和平衡易位携带者后代的几率较高,选择自然妊娠并进行产前诊断来获取健康后代是完全可行的。不同染色体发生易位其生育不平衡后代几率不同。     

夫妇双方染色体平衡易位致反复性流产1例

夫妇双方染色体平衡易位致反复性流产１例杨瑞芳王明毅王济周李毅（山东医科大学附属医院围产医学中心遗传室）染色体平衡易位是导致自然流产的重要原因之一。异常染色体可发生在夫妇任何一方，但双方同时发生平衡易位尚未见有报道。现报告一对患反复自然流产的夫妇，他们...     

反复自然流产的病因学研究

目的 探讨反复自然流产的发病原因。方法 对２０８例反复自然流产患者进行妇检、盆腔Ｂ超、感染因素的检查、性激素水平测定,患者丈夫进行精液常规检查,患者夫妇同时检查染色体核型、ＡＢＯ血型及血清ＩｇＧ抗体滴度水平、抗精子抗体并进行ＨＬＡ相容性研究。结果 在病因明确的反复自然流产中,解剖学因素占首位（２０．２％）,其次为感染性因素（１０．６％）,ＡＢＯ血型不合（９．１％）及内分泌因素（７．２％）等。原因不     

75对早期自然流产夫妇的细胞遗传学分析

本文收集自然流产夫妇共75对临床资料,发现5例染色体异常,占受检人数的3.33%,并检出3例随体区变异.复习有关文献并结合异常病例探讨,表明:平衡易位携带者是流产夫妇中最常見的染色体异常,其检出率与流产次数和发生时间有一定的关系,具有重要的临床意义.     

309对早期自然流产夫妇的染色体分析——附4例世界首报核型

目的 :分析早期自然流产与染色体异常核型的关系。方法 :检测 30 9对早期自然流产夫妇双方的外周血淋巴细胞染色体核型。结果 :早期自然流产夫妇中异常核型检出率明显高于普通人群 ,总检出率为 6 .95 %。染色体异常 2 0例 :其中平衡易位 18例 (4例为世界首报核型 ) ,增加额外小染色体 2例 ;染色体异态 2 3例 :9号染色体臂间倒位 7例 ,D、G组随体变异 2例 ,9、16号次缢痕异染色质区变异 2例 ,Y染色体异态 12例。结论 :染色体异常和异态是导致早期自然流产的重要原因之一 ,对早期自然流产夫妇进行染色体检查是必要的 ,可以寻找流产原因 ,为优生优育提供依据     

2178对自然流产史夫妇染色体分析

目的:分析自然流产史夫妇外周血染色体异常核型的种类及其在男女性中的分布特点。方法:检测2178对自然流产史夫妇外周血淋巴细胞染色体核型,分析比较染色体变异的种类、发生率及其在男、女性中的分布差异。结果:2178对(4356例)自然流产史夫妇中发现染色体异常539例(12.37%),其中男266例,女273例。染色体结构异常87例,其中相互易位最多见为58例(66.7%,58/87),有27例为世界首报染色体结构异常核型。其次为罗伯逊易位13例,倒位6例,插入、缺失等其他异常核型10例。染色体数目异常8例,包括2例标记染色体、1例XYY及5例不同类型的X染色体非整倍体嵌合。多态性改变444例中,D/G组染色体随体区变异最为多见,共271例(61.04%,271/444)。结论:自然流产史夫妇外周血染色体异常均有发生,男女性发生率并无明显差异,染色体异常以相互易位为主。染色体多态性发生率较高,对以自然流产史就诊的夫妇,有必要同时进行染色体检查,有助于病因的分析与诊断,并为临床咨询及后续生殖干预提供依据。     

Chromosome study of couples with repeated spontaneous abortions

The incidence of chromosomal abnormalities was evaluated in couples with a history of repeated abortions. The study included 14 couples with a history of 2 or more spontaneous abortions. Chromosome analysis was carried out on both marital partners from peripheral lymphocyte cultures. In every case, 30-62 metaphases were counted, and at last 20 karyotyped. Among the 14 couples, chromosome anomaly was found in 1 of the partners in 1 case. The patient, a 29-year-old female, was admitted to the hospital in the 36th week of her 10th pregnancy. In addition to an induced abortion and a premature delivery, her history included 7 spontaneous abortions at the 1st or 2nd month. Chromosome analysis of her peripheral blood revealed neither numerical nor structural aberations. In the 38th week, the patient gave birth ato a 3990 gm healthy boy whose karyotype of the cord blood also proved to be normal. The karyotype of the patient's husband revealed 45 chromosomes in 32 observed cells, and a chromosome was missing from each of the D and G groups. It was not possible to include in any of the groups a medium-sized, subterminal chromosome, diagnosed as D/G translocation. The husband proved to be a balanced D/G translocation carrier. When the pedigree was prepared, it was found that the younger sister of the husband had given birth to a child 1 month before term. Both the sister and her child were studied. The sister proved to be a balanced D/G translocation carrier. The child had translocational Down's syndrome: the D/G translocation occured in an unbalanced form. A table lists the results of chromosome investigations of cases of repeated abortions. Of 1066 married partners, chromosome aberations or variations responsible for multiple abortions were found in 70 (6.5%). Of these, 26 proved to be translocations. This incidence, 2-4%, is higher than the .4% in the general population. The results add credence to the argument that chromosome aberation may play a role in the causal background of recurring abortions. It is possible that with special staining procedures some aberations can be demonstrated in cases hitherto considered normal. In cases of repeated abortion, cytogenetic examination of both partners is routinely justified. In cases of chromosome aberations valuable data can be gained to serve as a basis for genetic counseling. When examining women with recurrent abortions, it should be possible to select patients to whom the possibility of intrauterine cytogenetic diagnosis can be offered.     

Analysis of chromosome abnormalities in sperm and embryos from two 45,XY,t(13;14)(q10;q10) carriers

Robertsonian translocation t(13q14q) is studied in sperm and embryos of two couples undergoing preimplantation genetic diagnosis (PGD) in which both males are carriers of the translocation. It is already known that the chances of achieving pregnancy for a translocation carrier are directly linked to the number of normal or balanced embryos available for replacement. In our work it was found that the frequency of balanced spermatozoa was almost identical in both patients (74 and 77%), and after PGD, the frequencies of abnormal embryos caused by the translocation were also similar. Sperm chromosome analysis in translocation carriers can provide a reasonable basis for estimating a baseline of chromosome abnormalities to be found in embryos during an assisted reproductive cycle. However, individual factors not linked to the translocation can also produce other chromosome abnormalities (mosaicism, haploidy, polyploidy) and may compromise the chances of achieving a viable pregnancy.     

Cytogenetic studies in couples with repeated spontaneous abortions

Chromosome studies were carried out on both partners of 509 couples with a history of two or more spontaneous abortions. 1) Twenty-six individuals (2.6%) were carriers of a major chromosome abnormality. This incidence is at least six to seven times higher than that in the general adult population. 2) Of these, 10 were reciprocal translocations, 10 robertsonian translocations and 6 numerical aberrations of gonosomes. None of the carriers showed abnormal phenotypes. 3) Chromosome aberrations were more frequent in the women than in their husbands. There were 19 abnormalities in females and 7 in males. 4) The use of banding techniques in chromosome analysis improves the detection of balanced reciprocal translocations. 5) Prenatal diagnosis was performed in 5 subsequent pregnancies of 4 balanced translocation carriers. The fetal karyotypes were 2 normal and 3 balanced translocations. It would seem reasonable to recommend chromosome analysis for couples with repeated spontaneous abortions.     

Cytogenetics of aborters and abortuses

783 aborters and 430 abortuses were studied in a prospective cytogenetic survey which attempted to link chromosome abnormalities and history of recurrent abortion. 425 female and 358 male spontaneous aborters and their 430 abortuses (310 were karotyped) showed 4 women and 2 men as balanced translocation carriers (3 Robertsonian and 3 reciprocal translocations) and a woman with an XXX karotype. 5 of the abortuses were successfully karotyped; 4 had inherited unbalanced translocation products, and the other had a balanced 13q14q translocation plus trisomy 18. Apparently, translocation chromosomes carried by aborters were transmitted to their abortuses. Structural chromosome abnormalities were found with higher frequency (.8%) among aborters than among the general adult population (.3%). Translocation carriers were more frequent among the aborters with histories of recurrent abortions (2.7%) as well as among aborters with a history of perinatal deaths (3.6%) than among those persons with no such histories (.6%). Data on 18 couples whose 2 or 3 successive spontaneous abortuses were karotyped are presented.     

SNP array-based analyses of unbalanced embryos as a reference to distinguish between balanced translocation carrier and normal blastocysts

Purpose

The purpose of the study is to validate a method that provides the opportunity to distinguish a balanced translocation carrier embryo from a truly normal embryo in parallel with comprehensive chromosome screening (CCS).

Methods

A series of translocation carrier couples that underwent IVF with single nucleotide polymorphism (SNP) array-based CCS on 148 embryos were included. Predictions of balanced or normal status of each embryo were made based upon embryonic SNP genotypes. In one case, microdeletion status was used to designate whether embryos were balanced or normal. In 10 additional cases, conventional karyotyping was performed on newborns in order to establish the true genetic status (balanced or normal) of the original transferred embryo. Finally, implantation potential of balanced or normal embryos was compared.

Results

Phasing SNPs using unbalanced embryos allowed accurate prediction of whether transferred embryos were balanced translocation carriers or truly normal in all cases completed to date (100 % concordance with conventional karyotyping of newborns). No difference in implantation potential of balanced or normal embryos was observed.

Conclusions

This study demonstrates the validity of a CCS method capable of distinguishing normal from balanced translocation carrier embryos. The only prerequisite is the availability of parental DNA and an unbalanced IVF embryo, making the method applicable to the majority of carrier couples. In addition, the SNP array platform allows simultaneous CCS for aneuploidy with the same platform and from the same biopsy. Future work will involve prospective predictions to select normal embryos with subsequent karyotyping of the resulting newborns.

     

Data on Families of Chromosome Translocation Carriers Ascertained Because of Habitual Spontaneous Abortion

Cytogenetic studies were performed on 1,180 individuals--490 couples + 200 females presenting with habitual spontaneous abortion (HSA). These revealed 24 abnormal results (2.03%)--15 were apparently balanced reciprocal translocations and 9 were Robertsonian translocations. Of 97 pregnancies among the translocation carriers, there were 10 living children and 87 pregnancy losses--a loss rate of 89.7%. There were 11 familial translocations. In 10 familial cases with a full family tree, there were 27 spontaneous abortions and 64 livebirths among the 30 adult translocation carrier relatives--a loss rate of 29.6%. This is twice the risk found in the general population but not as high as in the probands, who had 6 times the abortion rate in the general population. Mechanisms are suggested for this difference. The subsequent pregnancy history of 12 index translocation couples showed an apparently improved pregnancy outcome with 13 further fetal losses and 13 living children, over a follow-up time per patient ranging from 1-5.5 years. However, when the pregnancy losses at ascertainment were combined with postascertainment losses, the overall rate of pregnancy loss remained the same.     

Cytogenetic study in 50 couples with recurrent abortions

The presence of chromosome abnormalities in couples with repeated spontaneous abortion is known even if the phenomenon is far from a complete assessment. A cytogenetic investigation in 50 couples with a history of two or more spontaneous abortions is referred to in this study. A peripheral blood lymphocyte culture was harvested for each subject and the slides were stained by G- and C-banding. Of the 100 individuals examined, 4 were carriers of balanced translocations, 3 of which were of the Robertsonian type. A chromosomal fragility (chromatidic and/or chromosomic gaps) was seen in 2 cases. The incidence of balanced translocations found here is 8% which is near to the mode (about 9%) observed in previous studies. Those frequencies are greater than in the general population (0.1-0.4%). This indicates that balanced translocations have some importance in causing abortion while this is not the case for other chromosomal abnormalities (e.g. pericentric inversions). Thus, cytogenetic analyses should be recommended in couples with repeated spontaneous abortions, when clinical data fail to clarify the cause.     

Pregnancy outcomes of reciprocal translocation carriers who have a history of repeated pregnancy loss

Cytogenetic investigation of 2,324 Japanese couples with repeated pregnancy loss revealed that 4.91% of couples (n = 114) had chromosome abnormalities including reciprocal translocation (n = 74), Robertsonian translocation (n = 23), and inversion (n = 10). Parental reciprocal translocation was a significant predictor of subsequent miscarriage (adjusted odds ratio: 3.6, 95% confidence interval: 1.8-7.1), and most of the miscarriages of the carrier couples were inevitable because of abnormal karyotypes, despite appropriate treatments.