Application of CNVplex combined with STR assay for genetic etiology exploration in chorionic villus of recurrent spontaneous abortion / 重庆医学

Objective The study is to present a novel assay for rapid detection of fetal aneuploidies in chorionic villus for spontaneous abortion.Methods Fetal chorionic villus samples were collected from 60 cases of women diagnosed with recurrent spontaneous abortion (RSA) before 13 weeks gestation.All samples were analyzed using CNVplex (copy numbcr variations multiplex) assay and fluorescence in situ hybridization (FISH) in addition to chromosome analysis.All villi specimens were cell cultured and karyotyped to confirm the fetal chromosomal status.Results Among 48 successfully cultured and karyotyped samples,the chromosomal abnormality rate was 60.42 ％.The results of karyotyping and the CNVplex assay were identical,both yielding 20 cases of euploidies,23 autosomal aneuploidies,3 triplodies and 2 × monosomies(Tumer Syndrome).However,FISH obtained only 38 results identical to karyotyping.Two cases of deletion and duplication of chromosome were also identified by CNVplex but not always by karyotyping.As for non-mosaic and non structural abnormity samples,the concordance between cytogenetics and genoty ping was 100％ in CNVplex and 79.17％ in FISH.Conclusion With CNVplex combined with STR(short tandem repeat) assay,we can detect the aneuploidy abnormalities as effectively as routine karyotyping without the need for cell culture,while also analyzing deletions and duplications(larger than 5 Mbp) that are not always detected by karyotype analysis.Our study demonstrates that CNVplex assay is an efficient,convenient,and accurate method to explore the etiology of miscarriage.

Aneuploidia dos cromossomos sexuais: casos raros ou subdiagnosticados? / Sex chromosome aneuploidies: rare or under diagnosed?

As aneuploidias dos cromossomos sexuais geralmente compartilham muitas características fenotípicas e achados neuropsicológicos, entre eles anomalias da genitália externa e retardo mental e contemplam a gama de diagnóstico diferencial de dois distúrbios frequentes na população, que são a síndrome do X-frágil e o autismo. Justifica-se, portanto, que o cariótipo seja o primeiro exame genético a ser solicitado em casos de malformações congênitas, distúrbios da diferenciação sexual, problemas comportamentais ou retardo mental. Descrevemos dois casos clínicos de crianças com as síndromes 47,XYY e mos 49,XXXXY/46,XY, com o objetivo de contribuir para a disseminação de informações acerca do fenótipo e diagnóstico de anomalias dos cromossomos sexuais...

A Sri Lankan child with 49,XXXXY syndrome.

Pentasomy 49,XXXXY is a rare sex chromosome disorder usually presenting with ambigous genitalia, facial dysmorphism, mental retardation and a combination of cardiac, skeletal and other malformations. The incidence of the condition is estimated to be 1 in 85,000 male births. Previously, this condition was identified as a Klinefelter variant. The condition is suspected in a patient, by a combination of characteristic clinical findings, and the diagnosis is confirmed by chromosome culture and karyotyping. In the case we report here, the main presentation of ambiguous genitalia led to a suspicion of a sex chromosome aneuploidy which was subsequently confirmed by chromosomal analysis.

Clinical Assessment of Fluorescence in Situ Hybridization for Prenatal Diagnosis of Chromosomal Abnormalities / 实用妇产科杂志

Objective:To investigate the clinical efficacy of fluorescence in situ hybridization(FISH)in prenatal diagnosis of chromosomal aneuploidy.Methods:FISH and karyotyping analysis were done in 120 samples of amniotic fluid from pregnant women.Results:FISH analysis results were consistent with those of karyotyping,the dectecting rate can reach 100%for chromosomal aneuploidies.There was no significant difference in the preference for FISH or karyotying for prenatal diagnosis when facing high matemal age,multi-indications and other factors(P>0.05).FISH was better when biochemical datafor down's syndrome were positive (P=0.029),however karyotyping was better when there was abnormal fetal ultrasound scan(P=0.000).Conclusions:FISH can detect the chromosomal aneuploidy quickly and accurately,especially when biochemical data for down's syndrome were positive.FISH could be the first choice for prenatal diagnosis in the third trimester of high-risk pregnancy.

Effect of gonadotropins on chromosome aneuploidy, chromosome mosaicism & sex ratio in mouse preimplantation embryos.

Background & objectives: There are potential risks of major birth defect in IVF (in vitro fertilization) pregnancy as well as IVF-ICSI (intra cytoplasmic sperm injection) pregnancies in comparison with naturally conceived human pregnancies. This increase risk could be due to either gonadotropins used for ovarian stimulation or in vitro culture conditions or multiple pregnancy or combinations of all the factors. The effects of gonadotropins on chromosome aneuploidy, chromosome mosaicism and sex ratio on mouse preimplantation embryos were evaluated through the use of fl uorescence in situ hybridization (FISH). Methods: The study material consisted of 111 preimplantation mouse embryos (2-16 cell stage) in control group and 405 preimplantation mouse embryos in gonadotropin stimulated group from genetically identical Swiss Albino young (6-8 wk) mouse kept in a similar environmental conditions. The study was designed to investigate effect of gonadotropins on chromosome aneuploidy, chromosome mosaicism and sex ratio through the use of FISH technique using chromosome X, Y and 19 probes. All blastomeres of embryos in both groups were assessed. Results: Interpretable FISH results were obtained in 66 embryos in control group and 128 embryos in gonadotropin stimulated group. There was no excess of chromosome aneuploidy (only one case of sex chromosome trisomy in study group; 19, 19, X, Y, Y) or chromosome mosaicism or deviations in sex ratio between the two groups. However, deviation (1.36 M: 1 F in control group & 1.25 M : 1 F in study group) was seen from expected sex ratio (1 M : 1 F) i.e., skewed sex ratio in both the groups. Interpretation & conclusions: Our results showed that gonadotropins used for ovarian stimulation had no effects in causing increase in chromosome X, Y, 19 aneuploidy and mosaicism and skewing of sex ratio in mouse model. A large scale study with more FISH probes on a larger sample size need to be done to confi rm the findings.

Outcome of Preimplantation Genetic Diagnosis for Chromosome Aneuploidy and Genetic Disease / 대한불임학회지

OBJECTIVES: Chromosome aneuploidy is associated with recurrent abortion and congenital anomaly and genetic diseases occur repeatedly in the specific families. Preimplantation genetic diagnosis (PGD) can prevent aneuploidy or genetic disease by selecting normal embryos before implantation and is an alternative to prenatal diagnosis. The aim of this study is to assess the outcome of PGD cycles by using FISH or PCR, and to determine the clinical usefulness and values in patients with risk of chromosomal aneuploidy or genetic disease. MATERIALS AND METHODS: From 1995 to Apr. 2001, a total of 108 PGD cycles in 65 patients with poor reproductive outcome were analyzed. The indications of PGD were translocation (n=49), inversion (n=2), aneuploidy screening (n=7), Duchenne muscular dystrophy (n=5) and spinal muscular atrophy (n=2). PGD was applied due to the history of recurrent abortion, previous birth of affected child or risk of aneuploidy related to sex chromosome aneuploidy or old age. Blastomere biopsy was performed in 6~10 cell stage embryo after IVF with ICSI. In the single blastomere, chromosome aneuploidy was diagnosed by using FISH and PCR was performed for the diagnosis of exon deletion in DMD or SMA. RESULTS: The FISH or PCR amplification was successful in 94.3% of biopsied blastomeres. The rate of transferable balanced embryos was 24.0% in the chromosome translocation and inversion, 57.1% for the DMD and SMA, and 28.8% for the aneuploidy screening. Overall hCG positive rate per transfer was 17.8% (18/101) and clinical pregnancy rate was 13.9% (14/101) (11 term pregnancy, 3 abortion, and 4 biochemical pregnancy). The clinical pregnancy rate of translocation and inversion was 12.9% (11/85) and abortion rate was 27.3% (3/11). In the DMD and SMA, the clinical pregnancy rate was 33.3% (3/9) and all delivered at term. The PGD results were confirmed by amniocentesis and were correct. When the embryos developed to compaction or morula, the pregnancy rate was higher (32%) than that of the cases without compaction (7.2%, p<0.01). CONCLUSIONS: PGD by using FISH or PCR is useful to get normal pregnancy by reducing spontaneous abortion associated with chromosome aneuploidy in the patients with structural chromosome aberration or risk of aneuploidy and can prevent genetic disease prior to implantation.

Outcome of Preimplantation Genetic Diagnosis for Chromosome Aneuploidy and Genetic Disease / 대한불임학회지

OBJECTIVES: Chromosome aneuploidy is associated with recurrent abortion and congenital anomaly and genetic diseases occur repeatedly in the specific families. Preimplantation genetic diagnosis (PGD) can prevent aneuploidy or genetic disease by selecting normal embryos before implantation and is an alternative to prenatal diagnosis. The aim of this study is to assess the outcome of PGD cycles by using FISH or PCR, and to determine the clinical usefulness and values in patients with risk of chromosomal aneuploidy or genetic disease. MATERIALS AND METHODS: From 1995 to Apr. 2001, a total of 108 PGD cycles in 65 patients with poor reproductive outcome were analyzed. The indications of PGD were translocation (n=49), inversion (n=2), aneuploidy screening (n=7), Duchenne muscular dystrophy (n=5) and spinal muscular atrophy (n=2). PGD was applied due to the history of recurrent abortion, previous birth of affected child or risk of aneuploidy related to sex chromosome aneuploidy or old age. Blastomere biopsy was performed in 6~10 cell stage embryo after IVF with ICSI. In the single blastomere, chromosome aneuploidy was diagnosed by using FISH and PCR was performed for the diagnosis of exon deletion in DMD or SMA. RESULTS: The FISH or PCR amplification was successful in 94.3% of biopsied blastomeres. The rate of transferable balanced embryos was 24.0% in the chromosome translocation and inversion, 57.1% for the DMD and SMA, and 28.8% for the aneuploidy screening. Overall hCG positive rate per transfer was 17.8% (18/101) and clinical pregnancy rate was 13.9% (14/101) (11 term pregnancy, 3 abortion, and 4 biochemical pregnancy). The clinical pregnancy rate of translocation and inversion was 12.9% (11/85) and abortion rate was 27.3% (3/11). In the DMD and SMA, the clinical pregnancy rate was 33.3% (3/9) and all delivered at term. The PGD results were confirmed by amniocentesis and were correct. When the embryos developed to compaction or morula, the pregnancy rate was higher (32%) than that of the cases without compaction (7.2%, p<0.01). CONCLUSIONS: PGD by using FISH or PCR is useful to get normal pregnancy by reducing spontaneous abortion associated with chromosome aneuploidy in the patients with structural chromosome aberration or risk of aneuploidy and can prevent genetic disease prior to implantation.