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Kochhar PK, Ghosh P. Reproductive outcome of couples with recurrent miscarriage and balanced chromosomal abnormalities. J Obstet Gynaecol Res 2012; 39:113-20. [PMID: 22672580 DOI: 10.1111/j.1447-0756.2012.01905.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
AIM Despite known association of parental carriers of structural chromosomal rearrangements with a history of recurrent pregnancy loss (RPL), the possibility of having a miscarriage due to an unbalanced chromosomal aberration remains unknown. There has been limited research on the reproductive outcome of such couples. The present study was done to report the distribution of structural chromosome rearrangements in patients experiencing RPL and to describe subsequent pregnancy outcomes in the carriers. MATERIAL AND METHODS Chromosomal analysis was performed on blood samples from 788 individuals with RPL and distribution of chromosomal anomalies was studied. In couples found to have chromosomal rearrangements, pregnancy outcomes were recorded over 2 years. In the subsequent pregnancy, cytogenetic analysis was done on amniotic fluid (obtained at 16-20 weeks), or on miscarriage specimens (in pregnancies that failed to continue). RESULTS Chromosomal rearrangements were identified in 6.8% (54/788) cases (including 5.9% reciprocal translocations, 0.7% Robertsonian translocations, and 0.1% inversions). The risk of having a chromosomal aberration was not related to the number of previous miscarriages. Over the next 2 years, two-thirds of the 49 documented pregnancies resulted in a normal live birth, and one-third miscarried. Most miscarriages (56.2%) were euploid, two were trisomic and 12.5% had an unbalanced translocation. CONCLUSION In couples with no other cause of RPL other than a structural chromosomal rearrangement, nearly two-thirds are likely to have a normal outcome in subsequent pregnancy. Couples with pure abortion histories carry higher risk for cytogenetic abnormality than couples with normal children in addition to abortions.
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Affiliation(s)
- Puneet Kaur Kochhar
- Double Helix Cytogenetics and Reproductive Immunology Centre, New Delhi, India.
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2
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Kosaki R, Migita O, Takahashi T, Kosaki K. Two distinctive classic genetic syndromes, 22q11.2 deletion syndrome and Angelman syndrome, occurring within the same family. Am J Med Genet A 2009; 149A:702-5. [PMID: 19288551 DOI: 10.1002/ajmg.a.32666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We document a sib pair born to a mother with a reciprocal translocation, t(15;22)(q13;q11.2): the daughter had the Angelman syndrome phenotype associated with a maternally derived 15q deletion, and the son had a phenotype associated with a 22q deletion. Adjacent two-type segregation during gametogenesis in the mother can account for the unbalanced karyotypes of the siblings. From a tetravalent chromatid formed by normal chromosome 15, derivative chromosome 15, normal chromosome 22, and derivative chromosome 22, the daughter inherited chromosome 22 and derivative chromosome 22 and the son inherited chromosome 15 and derivative chromosome 15. The family is unique in that two distinctive genetic syndromes, 22q11.2 deletion syndrome and Angelman syndrome, occurred within the same family. The family is also elucidative from an educational standpoint in that major concepts of non-Mendelian inheritance (microdeletion, genomic imprinting, and reciprocal translocation) need to be considered to appreciate the inheritance pattern. Furthermore, the family illustrates the importance of cryptic rearrangements at the most proximal end of acrocentric chromosomes in the evaluation of siblings with multiple congenital anomaly-mental retardation phenotypes that are dissimilar among affected siblings. The situation is analogous to parental balanced translocation between the most "distal" segments of a chromosome, that is, the subtelomere region, a recently appreciated cause of familial recurrence of multiple congenital anomaly-mental retardation phenotype with a normal G-banding karyotype. We suggest that cryptic rearrangements at the most proximal end, analogous to those at the most distal end, should be considered as an appreciable cause of recurrent multiple congenital anomaly-mental retardation phenotype.
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Affiliation(s)
- Rika Kosaki
- Department of Clinical Genetics and Molecular Medicine, National Center for Child Health and Development, Tokyo, Japan
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3
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Midro AT, Wiland E, Panasiuk B, Leśniewicz R, Kurpisz M. Risk evaluation of carriers with chromosome reciprocal translocation t(7;13)(q34;q13) and concomitant meiotic segregation analyzed by FISH on ejaculated spermatozoa. Am J Med Genet A 2006; 140:245-56. [PMID: 16411217 DOI: 10.1002/ajmg.a.31083] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We performed the segregation analysis of a relatively large pedigree of t(7;13)(q34;q13) carriers together with the sperm karyotype analysis of the one carrier using a tri-color fluorescence in situ hybridization (FISH) method. The risk assessments for unfavorable pregnancy outcomes in a series of 36 pregnancies in eight reciprocal chromosome translocation (RCT) couples of carriers were estimated directly from a pedigree after ascertainment correction. The individual probability rate for unbalanced child was predicted according to Stengel-Rutkowski and co-workers. The unbalanced karyotypes in the form of monosomy 7q34-->qter and trisomy 13q13-->qter were detected among stillborn/early death newborns with holoprosencephaly (HPE), cyclopia and other malformations. Based on clinical description of unkaryotyped stillbirth progeny, it can be assumed that the phenotype distinctions were connected with the unbalanced karyotype from 2:2 segregation (monosomy 7q with trisomy 13q) and 3:1 segregation as interchange trisomy 13 (Patau syndrome). Probability rates for miscarriages, stillbirth/early death were 12.9 +/- 6% (4/31) and 29 +/- 8.2% (9/31), respectively. The results of the meiotic segregation pattern indicated the rate of unbalanced spermatozoa for about 60%, with the unusual high rate (29.4%) of 3:1 segregant (i.e., 13.4% of the tertiary segregation and 16% of the interchange segregation). Adjacent-1 segregation followed with 23.5% and adjacent-2 followed with 7.2% of analyzed spermatozoa. The high rate of unbalanced gametes in comparison to the number of stillborn/early death and miscarriages detected in pedigree suggests a strong selection against unbalanced chromosomal constitutions during fetal development. It corresponds to a very small probability rate (about 0.3%) of viable unbalanced progeny from 3:1 meiotic segregation predicted for maternal carriers. This knowledge can be used in genetic counseling of families with similar RCT ascertained in a different way.
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Affiliation(s)
- Alina T Midro
- Department of Clinical Genetics, Medical University Białystok, Białystok, Poland.
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4
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Takeno SS, Corbani M, Andrade JAD, Smith MDAC, Brunoni D, Melaragno MI. Duplication 4p and deletion 4p (Wolf-Hirschhorn syndrome) due to complementary gametes from a 3:1 segregation of a maternal balanced t(4;13)(p16;q11) translocation. ACTA ACUST UNITED AC 2004; 129A:180-3. [PMID: 15316961 DOI: 10.1002/ajmg.a.30224] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We present clinical and cytogenetic data on a family with a t(4;13)(p16;q11) translocation present in four generations. The balanced translocation resulted in one individual with monosomy 4p and one individual with trisomy 4p, due to 3:1 segregation. The male patient with trisomy 4p was fertile and transmitted the extra chromosome to his daughter.
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Affiliation(s)
- S S Takeno
- Genetics Division, Universidade Federal de São Paulo, São Paulo, SP, Brazil
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5
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McKenzie LJ, Cisneros PL, Torsky S, Bacino CA, Buster JE, Carson SA, Simpson JL, Bischoff F. Preimplantation genetic diagnosis for a known cryptic translocation: follow-up clinical report and implication of segregation products. Am J Med Genet A 2003; 121A:56-9. [PMID: 12900903 DOI: 10.1002/ajmg.a.20159] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This report describes preimplantation genetic diagnosis (PGD) of a couple with a known paternally-derived balanced cryptic translocation 46,XY.ish t(2q;17q)(210E14-,B37c1+;B37c1-,210E14+) in embryos from a couple who previously had a child with severe mental retardation and was previously described in this journal [Bacino et al., 2000]. This child inherited the unbalanced product of translocation from her father: 46,XX.ish der(2)t(2q;17q)pat(210E14-,B37c1+). The couple desired a normal offspring and sought PGD to avoid clinical pregnancy termination. They were treated three times with in vitro fertilization followed by PGD. Two sequential FISH hybridizations were performed. In the first hybridization, telomeric probes to 2q and 17q and a chromosome 17 centromere probe were employed. The second hybridization screened for maternal age-related aneuploidy (X,Y,13,18,21). Of the 18 informative embryos, only 4 (22%) were normal. The remaining 12 (67%) were abnormal; most with unbalanced products (10/12) from the paternally-derived rearrangement. The most frequent mode of segregation observed for this cryptic translocation was adjacent-1 (7/18, 39%). This suggests cryptic translocations are amenable to PGD and, as are traditional translocations, demonstrate higher frequencies of unbalanced segregants than the empiric risk of 10-15% observed at amniocentesis or chorionic villus sampling. Thus, cryptic translocations presumably behave like overt translocations, in that PGD must be performed on a relatively large number of embryos to assure even 2-3 transferable embryos.
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Affiliation(s)
- L J McKenzie
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas 77030, USA.
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6
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Wysocka B, Brozek I, Wierzba J, Kardaś I, Woźniak A, Kowalczyk J, Balcerska A, Limon J. Partial trisomy of distal 5q and partial monosomy of Xp as a result of mating between two translocation carriers: a female with a balanced translocation t(X;5)(p11;q31) and a male with a der(13;14)(q10;q10)--a case report and a family study. ANNALES DE GENETIQUE 2002; 45:143-6. [PMID: 12381446 DOI: 10.1016/s0003-3995(02)01124-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This paper presents the family of a dysmorphic child with the phenotypic features of Turner's syndrome and 5q trisomy, whose parents are both carriers of a balanced translocation. The parents' karyotypes are 46,X,t(X;5)(p11.1;q31) and 45,XY,der(13;14)(q10;q10), respectively.
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MESH Headings
- Child
- Chromosome Aberrations
- Chromosomes, Human, Pair 13
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 5
- Chromosomes, Human, X
- Female
- Humans
- In Situ Hybridization, Fluorescence
- Karyotyping
- Male
- Pedigree
- Sex Chromosome Aberrations
- Translocation, Genetic
- Trisomy
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Affiliation(s)
- Barbara Wysocka
- Department of Biology and Genetics, Medical University of Gdańsk, Poland
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7
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Wilson CJ, Oei PT. The use of a specific clinical history in counselling a family with the balanced translocation 46,XY,t(4;12)(p15.2;q21.3): viable offspring with partial monosomy 4p and trisomy 12q. Clin Genet 1998; 54:110-1. [PMID: 9727755 DOI: 10.1111/j.1399-0004.1998.tb03708.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Genetic Counseling and Prenatal Diagnosis. Human Genome Project. Hum Genet 1997. [DOI: 10.1007/978-3-662-03356-2_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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9
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Qumsiyeh MB. Impact of rearrangements on function and position of chromosomes in the interphase nucleus and on human genetic disorders. Chromosome Res 1995; 3:455-65. [PMID: 8581297 DOI: 10.1007/bf00713959] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A synthesis of numerous published data and my own observations reveal that chromatin structure in interphase is functional, dynamic and complex. I hypothesize that: (1) chromosome regions organize nuclear structures and thus their own environment (address themselves in sites and condensation patterns most appropriate for their functional state in the particular cell); (2) chromosome rearrangement could alter nuclear architecture and thus function; and (3) these ideas can explain the contribution of chromosome rearrangements, even in a balanced form, to human pathologic conditions.
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Affiliation(s)
- M B Qumsiyeh
- Duke University Medical Center, Cytogenetics Laboratory, Durham, NC 27710, USA
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10
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Cans C, Cohen O, Lavergne C, Mermet MA, Demongeot J, Jalbert P. Logistic regression model to estimate the risk of unbalanced offspring in reciprocal translocations. Hum Genet 1993; 92:598-604. [PMID: 8262520 DOI: 10.1007/bf00420946] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The aim of this study was to estimate the risk of viable unbalanced offspring for a parental carrier of reciprocal translocation. On a large computerized database of reciprocal translocations we used logistic regression to model this risk. The status of the progeny is the outcome variable. Explanatory covariates are cytogenetic characteristics of the translocation, age and sex of the parental carrier, and potential viability of the gametes. The results obtained by the logistic model demonstrate the important role of certain variables such as the sex of the parental carrier and the R band length of the translocated segments. Within the group of lower risk (risk of viable unbalanced offspring less than 5%), 97% of the individuals are correctly classified with this model. For this group, the choice prenatal diagnosis can be best discussed by considering both the risk for viable unbalanced offspring and the risk of induced abortion following prenatal diagnosis.
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Affiliation(s)
- C Cans
- Genetics Laboratory, Medical School, Joseph Fourier University Grenoble, La Tronche, France
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11
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Cotton C, Cummins M, Smith A. Alternate, adjacent 2 and 3:1 meiotic segregation products from a balanced t(13;18) (q12;q11) carrier. Clin Genet 1993; 44:193-5. [PMID: 8261649 DOI: 10.1111/j.1399-0004.1993.tb03878.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We present a case in which alternate, adjacent 2 and 3:1 meiotic segregations have occurred in the pregnancies of a female carrier of a balanced reciprocal translocation -46,XX,t(13;18) (q12;q11). Products of five conceptions effectively showed trisomy 18q, trisomy 18p or monosomy 18p. This is one of the rare rearrangements which can give rise to a variety of segregation modes including adjacent 2.
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Affiliation(s)
- C Cotton
- Department of Genetics, Children's Hospital, Camperdown, NSW, Australia
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12
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Tsuji K, Narahara K, Yokoyama Y, Ninomiya S, Yonesawa S, Hiramatsu Y, Masaoka H, Kudo N, Seino Y. Reproductive risk in mating between two translocation carriers: case report and review of the literature. AMERICAN JOURNAL OF MEDICAL GENETICS 1993; 46:524-8. [PMID: 8322814 DOI: 10.1002/ajmg.1320460513] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We conducted a study to determine the reproductive risk in a couple who were translocation carriers. This couple, who carried balanced reciprocal translocations, experienced habitual abortions. The wife had a karyotype of 46,XX,t(7;13)(p15.3;q12.3) and the husband of 46,XY,t(1;7)(p11.1;p11.1). Chromosome study of their fourth abortus demonstrated a chimera consisting of two cell lines with a 46,XY and a 46,XX,t(1;7)(p11.1;p11.1)pat, -13, + der(7)t(7;13)(p15.3;q12.3)mat, karyotype. A review of the literature indicates that the risk of having unbalanced live offspring or of spontaneous abortion/stillborns is similar in couples in whom both were translocation carriers and in couples in whom one individual was a translocation carrier. The apparent lack of increased reproductive failure may result from the selective disadvantage of aneusomic gametes at fertilization or very early spontaneous abortions of unbalanced conceptuses.
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Affiliation(s)
- K Tsuji
- Department of Pediatrics, Okayama University Medical School, Japan
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13
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Cans C, Cohen O, Mermet MA, Demongeot J, Jalbert P. Human reciprocal translocations: is the unbalanced mode at birth predictable? Hum Genet 1993; 91:228-32. [PMID: 8478005 DOI: 10.1007/bf00218261] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Two methods of prediction for the risk of unbalance at birth were tested on a large data base of reciprocal translocation (1376 families): the pachytene diagram predictive method (PDP method) and the discriminant method (D method). These method succeeded in correctly predicting the segregation mode in 66% of the data for the PDP method and in 80% of the data for the D method. The quality of chromosome material (in particular R bands) must be taken into account for more accurate prediction. Some difficulties still exist in predicting the 3:1 tertiary segregation mode, which can frequently be incorrectly classified as the adjacent 1 mode.
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Affiliation(s)
- C Cans
- Genetics Laboratory, Medical School, Joseph Fourier University, Grenoble, La Tronche, France
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14
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Phillips OP, Tharapel AT, Shulman LP, Simpson JL, Elias S. Segregation analysis and genetic counseling when both parents carry balanced chromosomal translocations. Fertil Steril 1991; 56:646-52. [PMID: 1915938 DOI: 10.1016/s0015-0282(16)54594-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To assess the risk of chromosomally abnormal offspring and discuss counseling approach when both parents carry balanced translocations. DESIGN Theoretical segregation analysis is performed and use of empiric data is used in genetic counseling. SETTING Patients are referred to Division of Reproductive Genetics at the University of Tennessee, Memphis. PATIENTS, PARTICIPANTS The mother, heterozygous for reciprocal translocation 46,XX, rcp(7;13)(p21;q22) and father, heterozygous for Robertsonian translocation 45,XY,rob(13q;14q) were referred for genetic counseling concerning risks of chromosomally abnormal offspring. INTERVENTIONS Segregation analysis, genetic counseling, and chorionic villus sampling. MAIN OUTCOME MEASURE(S) A cumulative risk was derived to use for counseling purposes. Cytogenetics using GTG-banding was performed on cultured chorionic villus cells. RESULTS Theoretical risk of this couple having chromosomally abnormal offspring was 40.5%. On the basis of empirical data and risk factors inherent in the specific translocations, the maternal contribution at midtrimester was 3.5%; the paternal contribution was 1% to 2%. The sum of these risks was used in counseling. CONCLUSIONS The fetus was found to be 46,XY,rcp(7;13)(p21;q22).
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MESH Headings
- Abortion, Habitual/genetics
- Adult
- Chromosomes, Human, Pair 13
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 21
- Chromosomes, Human, Pair 7
- Female
- Genetic Counseling
- Humans
- Male
- Pregnancy
- Translocation, Genetic
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15
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Kausch K, Haaf T, Köhler J, Schmid M. Complex chromosomal rearrangement in a woman with multiple miscarriages. AMERICAN JOURNAL OF MEDICAL GENETICS 1988; 31:415-20. [PMID: 3068990 DOI: 10.1002/ajmg.1320310221] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We report on a 23-yr-old healthy female with repeated miscarriages and a de novo complex chromosomal rearrangement (CCR) involving chromosomes 1, 2, 5 and 11 with 5 breakpoints. A review of cases reported in the last five yr is provided.
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Affiliation(s)
- K Kausch
- Department of Human Genetics, University of Würzburg, West Germany
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16
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Bowser-Riley SM, Griffiths MJ, Creasy MR, Farndon PA, Martin KE, Thomson DA, Larkins SA, Johnson RA, Watt JL. Are double translocations double trouble? J Med Genet 1988; 25:326-31. [PMID: 3290489 PMCID: PMC1050459 DOI: 10.1136/jmg.25.5.326] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Double translocation heterozygotes are rare, but need not necessarily pose more of a counselling problem than single reciprocal translocation heterozygotes. Nine cases of double translocation are presented, together with a review of the few reports published to date. An attempt is made to provide simple counselling guidelines in the assessment of the risk of producing a liveborn abnormal child. This is not based on theoretical considerations of segregation patterns, but extrapolated from what is known empirically about the viable segregation patterns in carriers of single reciprocal translocations. It assumes that there is no interference with the independent assortment of the two separate exchanges, unless a common participating chromosome is involved. The possibility of an interchromosomal effect has not been taken into consideration.
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Affiliation(s)
- S M Bowser-Riley
- Regional Cytogenetics Unit, Birmingham Maternity Hospital, Edgbaston
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17
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Porfirio B, Dallapiccola B, Terrenato L. Breakpoint distribution in constitutional chromosome rearrangements with respect to fragile sites. Ann Hum Genet 1987; 51:329-36. [PMID: 3447515 DOI: 10.1111/j.1469-1809.1987.tb01067.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In an attempt to investigate possible relationships between fragile site bands and chromosome abnormalities, we have analysed the distribution of 6391 breakpoints found in constitutional rearrangements. Were relative band lengths to be ignored, a general trend for breaks to be located in fragile site bands would be confirmed. On the other hand, no difference was detected between bands with or without fragile sites if the probability of breakage for each single band is assumed to be proportional to its length. Nevertheless, a number of bands with a great excess of breakage events were identified.
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Affiliation(s)
- B Porfirio
- Department of Public Health and Cell Biology, Tor Vergata University, Rome, Italy
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18
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Holmes-Siedle M, Ryynanen M, Lindenbaum RH. Parental decisions regarding termination of pregnancy following prenatal detection of sex chromosome abnormality. Prenat Diagn 1987; 7:239-44. [PMID: 3588542 DOI: 10.1002/pd.1970070403] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In the period of a retrospective study (1970-1984 inclusive) forty cases of sex chromosome aneuploidy were identified at amniocentesis in Oxford, England and in Kuopio, Finland; 25 of these pregnancies were subsequently terminated. A decision to continue was made more often for XYY and XXX karyotypes, by older mothers and older fathers, by couples with more previous children, and by couples living in England. A decision to terminate was made more often for XXY and non-mosaic 45,X karyotypes, by younger mothers and younger fathers, by couples with few previous children, in all cases with abnormal ultrasound findings, when post-amniocentesis counselling was given by an obstetrician, and by couples living in Finland. Previous miscarriages, or terminations of pregnancy, previous problems with infertility, marital status, or the type of counselling given before amniocentesis, appeared not to influence a couples' decision. Religious and ethical ideas were not studied systematically at the time and cannot be reported on.
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19
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Daniel A, Boué A, Gallano P. Prospective risk in reciprocal translocation heterozygotes at amniocentesis as determined by potential chromosome imbalance sizes. Data of the European Collaborative Prenatal Diagnosis Centres. Prenat Diagn 1986; 6:315-50. [PMID: 3774764 DOI: 10.1002/pd.1970060502] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The Date of the European Cooperative Prenatal Diagnosis Laboratories (Boué and Gallano, 1984) of 596 prenatal (amniocyte) diagnoses of familial rcp was examined as to relationships between balanced/unbalanced result and ascertainment, carrier parent and chromosome imbalance size (percentage haploid autosome length). Each rearrangement was graphed once with actual (unbalanced result) or potential (normal or balanced result) imbalances plotted with trisomy as the ordinate and monosomy as the abscissa. The graphed data was divided into 15 regions, each of 2.0 per cent trisomy and 0.75 per cent monosomy and the rate of unbalanced pregnancies determined for each region. The highest rates of chromosomally unbalanced progeny (excluding regions with inadequate data) were found closest to the origin (i.e. associated with the smallest imbalances) and these were for ascertainment category 1 (previous rcp unbalanced child) 22.3 per cent for maternal carriers and 39 per cent for paternal carriers. Overall in pooled data for this ascertainment category (without reference to the imbalance graphs) there were for paternal carriers 28.6 per cent unbalanced pregnancies and for maternal carriers 18.1 per cent. The graphed data, therefore, revealed the higher rates associated with some of the rcp with small potential (combined duplication/deficiency) imbalances. Lesser rates were observed for ascertainment category 2 (carrier parent with a history of recurrent miscarriage) with overall percentages of imbalanced progeny ranging from 2.7 (paternal carriers) to 4.7 (maternal carriers). Again, higher rates were revealed in graphed data for small potential imbalances. All unbalanced results for this group (ascertainment category 2) plotted in the region closest to the origin with rates of 16 per cent (maternal carriers) and 9.5 per cent (paternal carriers) in this region. Remarkably in both ascertainment groups 1 and 2 there was no significant difference in the size of the imbalanced segments for unbalanced progeny. In ascertainment group 1 this was (dup/def; mean +/- S.D.): 1.09 +/- 0.77/0.47 +/- 0.45 and in ascertainment group 2: 1.09 +/- 0.80/0.66 +/- 0.71. From the graphed data which arguably denote viability relationships, a trisomy was approximately 2.7 times as likely to survive until amniocentesis as a monosomy of equivalent size. It is proposed that given further data, risk estimates could be determined for rcp heterozygotes using the present approach where empiric data (from the family history or an analysed series of similar rcp) is not available.
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20
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De Arce MA, Grace PM, McManus S. A computer model for the study of segregation in reciprocal translocation carriers: application to 20 new cases. AMERICAN JOURNAL OF MEDICAL GENETICS 1986; 24:519-25. [PMID: 3755291 DOI: 10.1002/ajmg.1320240315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
We report on a computer program that, given the breakpoints and the chromosomes involved in a translocation, generates all the possible imbalanced gametes, calculates their corresponding imbalances, and arranges them in order of increasing imbalance. When compared to current, more cumbersome criteria from the literature, both methods agreed on 196 cases of 199 (greater than 98%). When compared to observed data from families with aneuploid offspring, both our program and the other reported methods yield a rate of accurate prediction of 87%. The use of the program is illustrated in 20 new translocations from our laboratory. The possible influence of crossing over in meiosis I in altering the gamete that is most likely to be passed to aneuploid live births is discussed.
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MESH Headings
- Abortion, Spontaneous/genetics
- Chromosome Aberrations
- Chromosomes, Human, 1-3
- Chromosomes, Human, 13-15
- Chromosomes, Human, 16-18
- Chromosomes, Human, 6-12 and X
- Female
- Genetic Counseling
- Humans
- Karyotyping
- Mosaicism
- Pregnancy
- Recurrence
- Translocation, Genetic
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Campana M, Serra A, Neri G. Role of chromosome aberrations in recurrent abortion: a study of 269 balanced translocations. AMERICAN JOURNAL OF MEDICAL GENETICS 1986; 24:341-56. [PMID: 3717213 DOI: 10.1002/ajmg.1320240214] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
We have studied a sample of 5,445 couples in which the woman was ascertained to have had two or more spontaneous abortions: 396 from our Cytogenetics Unit (present series) and 5,049 from the literature (literature series). In approximately 5% of these couples one of the members was a carrier of a balanced translocation, either reciprocal (2/3 of cases) or Robertsonian (1/3). In 1% of the couples there were other chromosome anomalies, mostly gonosomal aneuploidies or mosaicisms. A pericentric inversion of the heterochromatic region of chromosome 9 was present in 3% of the couples of the present series and in 1% of the literature series. The number of female carriers exceeded significantly that of males. The probability for one member of the couple to be a carrier increased with the number of abortions at the time of ascertainment, but it does not seem modified by the concomitant presence of term pregnancies. The analysis of the cytogenetic findings in 80 cases of Robertsonian and 156 cases of reciprocal translocations suggests that some chromosomes are preferentially involved, and that in reciprocal translocations the breakpoints are not distributed at random on the chromosome arms. There is an excess of breakpoints on chromosomes 6, 7, and 22 and a dearth on chromosome 12. This distribution is significantly different from that of a sample of reciprocal translocations ascertained for a malformed child. In both samples the breakpoints seem associated with fragile sites more frequently than expected by chance. An analysis of the potential and effective chromosome imbalance suggests that in subjects with unbalanced chromosomes survival is correlated with a minimum imbalance.
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24
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Fryns JP, Kleczkowska A, Kubień E, Van den Berghe H. Excess of mental retardation and/or congenital malformation in reciprocal translocations in man. Hum Genet 1986; 72:1-8. [PMID: 3943858 DOI: 10.1007/bf00278808] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In this report the Leuven experience (1970-1984) on reciprocal translocations is summarized. A total of 153 unrelated index patients, carriers of different types of reciprocal translocations, and their families were investigated. Familial reciprocal, apparently balanced translocations were found in 75 unrelated families bringing the total numbers of translocation carrier parents and their offspring to 132 and 445, respectively. In 61.5% of the patients the reciprocal translocation was detected after the birth of a malformed child with unbalanced karyotype or through investigation because of recurrent spontaneous abortions, stillbirths, or infertility. In 41 patients (28 familial and 13 de novo), however, the reciprocal balanced translocation was found to be associated with mental retardation and/or congenital malformations (MR/CM) which is significantly higher than expected. This excess of MR/CM in de novo and familial balanced translocation carriers is illustrated and discussed.
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Magnuson T, Debrot S, Dimpfl J, Zweig A, Zamora T, Epstein CJ. The early lethality of autosomal monosomy in the mouse. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1985; 236:353-60. [PMID: 4086989 DOI: 10.1002/jez.1402360313] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Using male mice doubly heterozygous for pairs of Robertsonian translocation chromosomes that have one arm in common, mouse embryos monosomic for 11 of the 19 autosomes have been generated. All of these monosomies result in death prior to or during the implantation period, with only rare survivors being detected 6 days after fertilization. For some of the monosomies the onset of lethality can be detected during the third or fourth day of development, but others do not begin to die until sometime after the late blastocyst stage on day 4. Retardation of development, as revealed by decreased cell numbers, is often detectable prior to or after the onset of the lethal period. The period during which death occurs may spread over several days and does not coincide with any of the developmental landmarks of the pre- or peri-implantation period. Genetic factors that may affect the rate of cellular proliferation or other aspects of embryonic development appear to play an important role in determining exactly when individual monosomies result in death. The universal early lethality of the autosomal monosomies leads to the conclusion that a large number of loci scattered over all of the autosomes are involved in processes that are so concentration dependent that a 50% reduction is sufficient to produce very serious consequences.
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