Sex Differences in Attitudes Toward Marriage and Childbearing Based on the Assumption of Being BRCA1/2 Mutation Carriers Among Young People / 한국유방암학회지

Purpose@#This study investigated changes in attitudes toward marriage and childbearing assuming a BRCA1/2 mutation carrier status among healthy, unmarried individuals in Korea. @*Methods@#A nationally representative sample of healthy, unmarried individuals aged 20–39 years was surveyed. A questionnaire on marriage and childbearing intentions was administered to the participants before and after providing them with information on BRCA1/2 mutation carriers’ breast and ovarian cancer risks and their autosomal dominant inheritance pattern. The participants were asked about their attitudes toward childbearing through preimplantation genetic diagnosis (PGD). @*Results@#Of the participants who initially wanted to marry, the assumption that they or their partners had BRCA1/2 mutation caused 25.3% to no longer want to get married and 36.2% to change their attitude from wanting to bear children to no longer wanting them. Females were more likely than males to change their attitudes toward marriage and childbearing. The participants who had negative attitudes toward genetic testing were more likely to change their attitudes regarding marriage and childbearing than those who were favorable toward both disclosure and testing. More than 50% of the participants who did not want children were willing to bear children through PGD when it was assumed that they were BRCA mutation carriers. @*Conclusion@#On the assumption of being carriers, general, young, and healthy females were more likely than males to negatively change their attitudes toward marriage and childbearing. Public education on the implications of living with mutation carriers and reproductive options may be required.

Attitudes toward Risk-Reducing Mastectomy and Risk-Reducing Salpingo-oophorectomy among Young, Unmarried, Healthy Women in Korea / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#This study investigated the attitudes toward risk-reducing mastectomy (RRM) and risk-reducing salpingo-oophorectomy (RRSO) as cancer prevention options for BRCA1/2 carriers in healthy, young, unmarried Korean women. @*Materials and Methods@#A nationally representative sample of 600 women, aged 20-39 years, completed a questionnaire on sociodemographic variables, preference for genetic testing, and intention to undergo risk-reducing surgeries after receiving information on the cancer risk of BRCA1/2 mutations and benefits of risk-reducing surgeries. @*Results@#A total of 54.7% and 57.7% had the intention to undergo RRM and RRSO, respectively, on the assumption that they were BRCA1/2 carriers. Older age and no intention to undergo genetic testing were associated with a reduced likelihood of undergoing RRM (odds ratio [OR], 0.30; 95% confidence interval [CI], 0.14 to 0.61 for age 35-39 years and OR, 0.35; 95% CI, 0.20 to 0.62 for no intention for genetic testing) and RRSO (OR, 0.39; 95% CI, 0.19 to 0.79 for age 35-39 years and OR, 0.30; 95% CI, 0.17 to 0.53 for no intention for genetic testing). Women who chose to be single were likely to undergo risk-reducing surgeries (OR, 1.67; 95% CI, 1.07 to 2.60 for RRM and OR, 1.56; 95% CI, 1.00 to 2.44 for RRSO). @*Conclusion@#More than 50% of healthy, unmarried, young Korean women were inclined to undergo prophylactic surgeries if they were BRCA1/2 mutation carriers. Further studies on decision-making process for cancer prevention in individuals at high risk for cancer need to be conducted.

Role of fetal ultrasound in prenatally diagnosed de novo balanced translocations

PURPOSE: This study aimed to investigate fetal ultrasonographic findings in cases of prenatally diagnosed de novo balanced translocations and the role of fetal ultrasound in prenatal genetic counseling. MATERIALS AND METHODS: We collected cases with de novo balanced translocations that were confirmed in chorionic villus sampling, amniocentesis, and cordocentesis between 1995 and 2016. A detailed, high-resolution ultrasonography was performed for prediction of prognosis. Chromosomes from the parents of affected fetuses were also analyzed to determine whether the balanced translocations were de novo or inherited. RESULTS: Among 32,070 cases with prenatal cytogenetic analysis, 27 cases (1/1,188 incidence) with de novo balanced translocations were identified. Fourteen cases (51.9%) showed abnormal findings, and the frequency of major structural anomalies was 11.1%. Excluding the major structural anomalies, all mothers who continued pregnancies delivered healthy babies. CONCLUSION: Results of a detailed, high-resolution ultrasound examination are very important in genetic counseling for prenatally diagnosed de novo balanced translocations.

Prenatal diagnosis of interchromosomal insertion of Y chromosome heterochromatin in a family

Interchromosomal insertion of Y chromosome heterochromatin in an autosome was identified in a fetus and a family. A fetal karyotype was analyzed as 46,XX,dup(7)(?q22q21.1) in a referred amniocentesis at 16 weeks of gestation for advanced maternal age. In the familial karyotype analyses for identification of der(7), the mother, the first daughter and the maternal grandmother showed the same der(7) as the fetus's. CBG-banding was positive at 7q22 region of der(7) that indicated inserted material was originated from heterochromatin. The origin of heterochromatic insertion region in der(7) of the fetus and the mother was found in Yq12 region by fluorescent in situ hybridization with a DYZ1 probe. In the specific analysis of Y chromosomal heterochromatic region of ins(7;Y) of the mother, 15 sequence tagged sites from Yp11.3 region including SRY to Yq11.223 region was not detected. Final karyotypes of the mother, the first daughter and the maternal grandmother were reported as 46,XX,der(7)ins(7;Y)(q21.3;q12q12). All female carriers of ins(7;Y) in the family showed normal phenotype and the mother and the maternal grandmother were fertile. A healthy girl was born at term. We report a rare case of familial interchromosomal insertion of Y chromosome heterochromatin detected only in female family members with normal phenotype that was diagnosed prenatally.

Three cases of rare SRY-negative 46,XX testicular disorder of sexual development with complete masculinization and a review of the literature

PURPOSE: To identify the clinical characteristics of SRY-negative male patients and genes related to male sex reversal, we performed a retrospective study using cases of 46,XX testicular disorders of sex development with a review of the literature. MATERIALS AND METHODS: SRY-negative cases of 46,XX testicular disorders of sex development referred for cytogenetic analysis from 1983 to 2013 were examined using clinical findings, seminal analyses, basal hormone profiles, conventional cytogenetic analysis and polymerase chain reaction. RESULTS: Chromosome analysis of cultured peripheral blood cells of 8,386 individuals found 19 cases (0.23%) with 46,XX testicular disorders of sex development. The SRY gene was confirmed to be absent in three of these 19 cases (15.8%). CONCLUSION: We report three rare cases of SRY-negative 46,XX testicular disorders of sex development. Genes on autosomes and the X chromosome that may have a role in sex determination were deduced through a literature review. These genes, through differences in gene dosage variation, may have a role in sex reversal in the absence of SRY.

An unusual de novo duplication 10p/deletion 10q syndrome: The first case in Korea

We herein report an analysis of a female baby with a de novo dup(10p)/del(10q) chromosomal aberration. A prenatal cytogenetic analysis was performed owing to abnormal ultrasound findings including a choroid plexus cyst, prominent cisterna magna, and a slightly medially displaced stomach. The fetal karyotype showed additional material attached to the terminal region of chromosome 10q. Parental karyotypes were both normal. At birth, the baby showed hypotonia, upslanting palpebral fissures, a nodular back mass, respiratory distress, neonatal jaundice and a suspicious polycystic kidney. We ascertained that the karyotype of the baby was 46,XX,der(10)(pter-->q26.3::p11.2-->pter) by cytogenetic and molecular cytogenetic analyses including high resolution GTG- and RBG-banding, fluorescence in situ hybridization, comparative genomic hybridization, and short tandem repeat marker analyses. While almost all reported cases of 10p duplication originated from one of the parents with a pericentric inversion, our case is extraordinarily rare as the de novo dup(10p)/del(10q) presumably originated from a rearrangement at the premeiotic stage of the parental germ cell or from parental germline mosaicism.

Prenatal Diagnosis of Chromosome 22q11.2 Deletions: Experiences in a Single Institution

PURPOSE: This study was designed to determine the frequency and echocardiographic findings of 22q11.2 deletions in fetuses with cardiac defects on fetal ultrasound or familial backgrounds of 22q11.2 deletions. MATERIALS AND METHODS: We retrospectively reviewed the medical and ultrasonographic records of 170 fetuses that underwent fluorescence in situ hybridization (FISH) analysis for chromosome 22q11.2 deletions between February 2001 and April 2013. RESULTS: Among 145 fetuses with cardiac defects, six (4.1%) had 22q11.2 deletions. Deletions of 22q11.2 were detected in 6 (5%) of the 120 fetuses with conotruncal defects: 5 (8.9%) of 56 with tetralogy of Fallot (TOF) and 1 (5.9%) of 17 with double outlet right ventricle (DORV). No deletions were found in cases of pulmonary atresia, truncus arteriosus, right aortic arch, or transposition of the great arteries. No 22q11.2 deletions were found in non-conotruncal cardiac malformations. Among 25 fetuses with familial backgrounds of 22q11.2 deletions, one (4%) had a maternally inherited 22q11.2 deletion with no cardiac findings. CONCLUSION: Knowledge of the frequency and echocardiographic findings of 22q11.2 deletions might be helpful for prenatal genetic counseling. It is advisable to perform FISH analysis for 22q11.2 deletions in pregnancies exhibiting conotruncal cardiac defects such as TOF or DORV.

Paracentric Inversions Found in Prenatal Diagnosis

PURPOSE: This study was designed to confirm whether the paracentric inversions of fetuses and parents may be harmless. MATERIALS AND METHODS: We report 10 cases (0.14%) with paracentric inversions among 7,181 prenatal cases observed during prenatal diagnosis performed at Cheil General Hospital between January 2009 and June 2013. We used cytogenetic GTL- and RBG-banding techniques. RESULTS: Of the 10 cases, nine cases were transmitted from each of the parents, and one case was de novo. Nine cases were phenotypically normal up to one month of age after birth. One case was lost to follow-up. We present prenatal diagnosis and follow-up examination of the fetuses with paracentric inversion. CONCLUSION: Based on our cases, most paracentric inversions are considered to be harmless. The precise identification of paracentric inversions might be clinically important and helpful for genetic counseling.

Analysis of Parental Decisions Based on Sex Chromosome Abnormalities Detected Prenatally: A Ten-year update (2001-2010)

PURPOSE: The aim of this study was to analyze parental decisions regarding pregnancies in which the fetus had sex chromosome abnormalities (SCA) over a ten-year period. MATERIALS AND METHODS: We collected and reviewed records from our hospital for 2001-2010 and a genetic specialist provided-genetic counseling. RESULTS: We diagnosed 130 cases (0.71%) with SCA out of 18,376 prenatal cases from 2001 to 2010. We reviewed the records and the results of all pregnancies. We also included cases (n=84) of apparently normal anatomic fetuses to analyze the factors influencing parental decisions. We excluded 34 cases with an obvious anomaly or a presumably bad outcome and 12 cases that were not followed up. Forty-three couples (51.2%) continued their pregnancies while forty-one (48.8%) terminated them. Of 38 mosaicism cases, 21 (55.3%) were continued. Among the 20 pregnancies assisted by reproductive techniques, 15 (75%) were continued (P=0.02). More pregnancies were continued when genetic counseling was provided (61.9%) compared to cases in which it was not provided (19%) (P=0.01). CONCLUSION: Genetic counseling is important in providing appropriate information to parents. Establishing guidelines and protocols will help both obstetricians and parents to make informed decisions.

A Prenatal Case of Paracentric Inversion of Chromosome 18, inv(18)(q21.1q22)

Paracentric inversion of chromosome 18 is a rare cytogenetic abnormality. The vast majority of paracentric inversions are harmless and the offspring of paracentric inversion carriers have only slightly elevated risks for unbalanced karyotypes. However, various clinical phenotypes are seen due to breakpoint variation or recombination. We report a prenatally detected case of familial paracentric inversion of chromosome 18, inv(18)(q21.1q22), with normal clinical features.

A Prenatal Case of Paracentric Inversion of Chromosome 18, inv(18)(q21.1q22)

Paracentric inversion of chromosome 18 is a rare cytogenetic abnormality. The vast majority of paracentric inversions are harmless and the offspring of paracentric inversion carriers have only slightly elevated risks for unbalanced karyotypes. However, various clinical phenotypes are seen due to breakpoint variation or recombination. We report a prenatally detected case of familial paracentric inversion of chromosome 18, inv(18)(q21.1q22), with normal clinical features.

Rarely Observed Jumping Translocation in Spontaneous Abortion

Jumping translocations (JT) are chromosomal rearrangements involving one donor chromosome and several recipient chromosomes. While JTs are frequently observed as acquired chromosomal abnormalities in hematologic malignancies, constitutional JTs are only rarely reported. We report two cases of constitutional JT in chorionic villi derived from the products of conception. The karyotype of the first case was 46,XY,add(18)(p11.1)[61]/45,XY,der(18;21)(q10;q10)[32]/46,XY,-18,+mar[16]/46,XY,i(18)(q10)[9]/45,XY,der(15;18)(q10;q10)[6]/46,XY,+1,dic(1;18)(p22;p11.1)[2]/45,XY,der(13;18)(q10;q10)[1]/46,XY[32]. The donor was a chromosome 18. The recipient chromosomes were chromosomes 1, 13, 15, 18 and 21. In the second case, the karyotype was 46,XY,der(22)t(9;22)(q12;q13)[22]/46,XY,der(22)t(1;22)(q21;q13) [13]/46,XY,add(22)(q13)[5]/46,XY[23]. The donor was a chromosome 22 and recipients were chromosomes 1 and 9. Both cases were de novo. The breakpoints of chromosomes were mostly in centromeric regions, pericentromeric regions, or telomeric regions. Normal cell lines were observed in both cases. This report supports the prior findings that the unstable nature of JT, resulting in chromosomal imbalance, most likely contributed to these early miscarriages.

Monocentric Derivative Y Chromosome with Duplication of the SRY Gene in an Azoospermic Male

Structural abnormalities of the Y chromosome affect normal testicular differentiation and spermatogenesis. The present case showed a rare monocentric derivative Y chromosome with partial duplication of Yp including the SRY gene and deletion of Yq12 heterochromatin. The karyotype was 46,X,der(Y) (pter-->q11.23::p11.2-->pter).ish der(Y)(DYZ3+,DYZ1-,SRY++), confirmed through a FISH study. Even though the patient possessed an abnormal Y chromosome, testicular biopsy showed normal testicular volumes in the proband, with gonadal hormonal levels in the normal range but bilateral varicocele and hypospermatogenesis. We speculate that the abnormal Y chromosome arose from sister chromatids during Y chromosome recombination or intra chromosomal NAHR (non-allelic homologous recombination) during meiosis in the patient's father or in the very early stages of embryogenesis. The derivative Y chromosome might interfere in the meiotic stage of spermatogenesis, leading to the developmental arrest of germ cells. The present case illustrates that the infertility phenotype can have various causes. Also, it emphasizes the importance of accurate and various genetic analyses and could aid in male infertility treatment.

Prenatally Diagnosed Uncommon Mosaic Autosomal Trisomy

Prenatal diagnosis of rare autosome mosaicism involvingchromosomes other than chromosome 13, 18, 21 or the sex chromosome is encountered prognostic dilemma during genetic counseling. We report four cases of level III uncommon mosaicism of trisomy 5, 16 and 20,diagnosed prenatally. In case 1 with mosaic trisomy 20, there was a higher mosaic ratio of trisomy 20 in the repeat amniocentesis (62.1%) than in the first (36.6%) with normal fetal ultrasound finding except for a relatively small aorta on a 3-vessel view of the fetal heart. Case 2 showed a low rate of mosaic trisomy 20 (5.25%) in cultured amniocytes but normal karyotype in the repeat amniocentesis, who delivered a normal healthy baby. Case 3 showed a 13.6% of trisomy 16 mosaicism in the 30 cells of cultured amniocytes. Sixty cells from a fetal blood sample at termination showed non-mosaic 46,XX normal karyotype, while skin fibroblasts had 22.5% trisomy 16 in 40 metaphases. The autopsy showed ventricular septal defect (VSD). Case 4 with low grade mosaicism (10.5%) of trisomy 5 resulted in elective termination, though the ultrasoumd showed growsly normal fetus. Although level III mosaicism is regarded as true mosaicism, it is difficult to predict the outcome of the fetus with rare mosaic autosome trisomy. Therefore mosaic autosome trisomy of fetus should be carefully interpreted with more various approaches including repeat sampling and targeted fetal ultrasound.

Prenatal Diagnosis of the 22q11.2 Duplication Syndrome

The 22q11.2 duplication syndrome is an extremely variable disorder with a phenotype ranging from normal to congenital defects and learning disabilities. Recently, the detection rate of 22q11.2 duplication has been increased by molecular techniques, such as array CGH. In this study, we report a familial case of 22q11.2 duplication detected prenatally. Her first pregnancy was terminated because of 22q11.2 duplication detected incidentally by BAC array CGH. The case was referred due to second pregnancy with same 22q11.2 duplication. We perfomed repeat amniocentesis for karyotype and FISH analysis. Karyotype analysis from amniocytes and parental lymphocytes were normal, while FISH analysis of interphase cells presented a duplication of 22q11.2 in the fetus and phenotypically normal mother. The fetal ultrasound showed grossly normal finding. After genetic counseling about variable phenotype with intrafamilial variability with 50% recurrence rate, the couple decided to continue the pregnancy. The newborn had no apparent congenital abnormalities until 2 weeks after birth. We recommend that family members of patients with a 22q11.2 duplication be tested by the interphase FISH analysis. Also, we point out the importance of genetic counseling and an evaluation of the clinical relevance of diagnostic test results.

Pericentric Inversion of the X Chromosome in a Male with Azoospermia and in the Family of a Pregnant Female Carrier

We report on two cases of pericentric inversion of X chromosome. The cases were found in a 40-year- old man with azoospermia and in a family of a 38-year-old pregnant woman. The first case with 46,Y,inv(X)(p22.1q27) had concentrations of LH, prolactin, estradiol, and testosterone that were within normal ranges; however, FSH levels were elevated. Testis biopsy revealed maturation arrest at the primary and secondary spermatocytes without spermatozoa. There were no microdeletions in the 6 loci of chromosome Y. For the second case, the cytogenetic study of the pregnant woman referring for advanced maternal age and a family history of inversion X chromosome was 46,X,inv(X)(p22.11q27.2). The karyotype of her fetus was 46,X,inv(X)(p22.1q27). Among other family members, the karyotypes of an older sister in pregnancy and her fetus were 46,X,inv(X)(p22.11q27.2), and 46,Y,inv(X), respectively. The proband's father was 46,Y,inv(X)(p22.11q27.2). All carriers in the family discussed above were fertile and phenotypically normal. In addition, the ratio of inactivation of inv(X) by RBG-banding was discordant between the two sisters, with the older sister having only 4.1% of cells carrying inactivated inv(X) while the proband had a 69.5% incidence of late replicating inv(X). Therefore, we suggest that the cause of azoospermia in the first case might be related to inversion X chromosome with positional effect. Also, the family of the second case showing normal phenotype of the balanced inv(X) might be not affected any positional effect of genes.

Prenatal diagnosis of a de novo ring chromosome 11

A 36-year-old pregnant woman was referred for amniocentesis at 19.5 weeks gestation because of advanced maternal age and evidence of increased risk for Edward syndrome in the maternal serum screening test. Cytogenetic analysis of the cultured amniotic fluid cells revealed mosaicism for ring chromosome 11: 46,XX,r(11)[65]/45,XX,-11[16]/46,XX[34]. Parental karyotypes were normal. A targeted ultrasound showed intrauterine growth restriction (IUGR). Cordocentesis was performed to characterize the ring chromosome and to rule out tissue specific mosaicism. Karyotype was confirmed as 46,XX,r(11) (p15.5q24.2)[229]/45,XX,-11[15]. And a few new form of ring were detected in this culture. The deletion of subtelomeric regions in the ring chromosome were detected by fluorescent in situ hybridization (FISH). The pregnancy was terminated. The fetal autopsy showed a growth-retarded female fetus with rocker bottom feet. We report a case of prenatally detected a de novo ring chromosome 11.

Maternal Serum and Amniotic Fluid Inhibin A Levels in Women who Subsequently Develop Severe Preeclampsia

The purpose of this study was to evaluate whether maternal serum (MS) and amniotic fluid (AF) inhibin A levels are elevated in patients who subsequently develop severe preecalmpsia, and to investigate the correlation between MS and AF inhibin A levels in the second trimester. The study included 40 patients who subsequently developed severe preecalmpsia and 80 normal pregnant women. Inhibin A levels in MS and AF were measured with enzyme-linked immunosorbent assay (ELISA). The MS and AF inhibin A levels in patients who developed severe preeclampsia were significantly higher than those in the control group (both for p<0.001). There was a positive correlation between MS and AF inhibin A levels in patients who developed severe preeclampsia (r=0.397, p=0.011), but not in the control group (r=0.185, p=0.126). The best cutoff values of MS and AF inhibin A levels for the prediction of severe preeclampsia were 427 pg/mL and 599 pg/mL, respectively; the estimated ORs that were associated with these cut-off values were 9.95 (95% CI 3.8-25.9, p<0.001) and 6.0 (95% CI 2.3-15.8, p<0.001). An elevated level of inhibin A in MS and AF at the time of second trimester amniocentesis may be a risk factor for the subsequent development of severe preeclampsia.

Rapid Prenatal Diagnosis of Down Syndrome Using Quantitative Fluorescent PCR in Uncultured Amniocytes

Rapid prenatal diagnosis of common chromosome aneuploidies have been successful through quantitative fluoresent PCR (QF-PCR) assays and small tandem repeat (STR) markers. The purpose of our study was to investigate the clinical feasibility for rapid prenatal detection of Down syndrome using the quantitative fluorescent PCR in uncultured amniocytes. DNA was extracted from uncultured amniotic fluid of normal karyotype (n=200) and of Down syndrome (n=21). It was amplified using QF-PCR with four STR markers located on chromosome 21. Among normal samples, the ranges of diallelic peaks for at least one STR marker were 1.0-1.3 for D21S11, 1.0-1.4 for D21S1411 and 1.0-1.5 for D21S1270. Down syndrome samples showed trisomic triallelic patterns or trisomic diallelic patterns. The sensitivity, specificity, and efficiency of the assay for detecting Down syndrome were 95.4%, 100%, and 99.5%, respectively. Rapid prenatal diagnosis of Down syndrome using QF-PCR is a reliable technique that aids clinical management of pregnancy.

De novo Chromosomal Aberrations in the Fetus; Genetic Counseling and Clinical Outcome

The aim of this study was to examine the incidence and clinical outcome of de novo chromosomal aberrations retrospectively and provide useful data for genetic counseling in the prenatal cytogenetic diagnosis. We found 17 cases of de novo chromosomal aberrations in 5,501 cases of prenatal cytogenetic analysis and reviewed the karyotype, further study, medical records, fetal ultrasound findings and clinical outcomes. Out of the 17 de novo chromosomal aberrations, 5 had balanced reciprocal translocations and 12 had unbalanced translocations characterized as deletion, addition, or marker. In the case of the five balanced reciprocal translocations, 3 cases without abnormal ultrasound findings were carried to term after comprehensive genetic counseling. Neonates were phenotypically normal and clinical examinations were normal. Two cases with abnormal ultrasound findings were terminated therapeutically. Twelve cases of unbalanced translocations were terminated except one case with a mosaic marker chromosome. High resolution fetal ultrasound and detailed cytogenetic and molecular study will be adjunctive tools for predicting the karyotype/phenotype correlations of fetuses with de novo chromosomal aberrations, although they have limitation to find all phenotypic effects.