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: ...

We report the results of the first major study of applying quantitative fluorescence polymerase chain reaction (QF-PCR) assays for the detection of major chromosome numerical disorders. The QF-PCR tests were performed on a total of 247 chorionic villus samples, which were analysed blind, without any knowledge of the results obtained using conventional cytogenetic analysis. The aims of this inve...

BACKGROUND Tetrasomy 18p is a very rare chromosomal disorder and is the result of a spontaneous mutation early in embryonic development in most of the cases. This condition is characterised by the presence of a supernumerary 18p isochromosome (i(18p)) in all or some cells of the affected individual. It has a prevalence of 1/180000 live births and affects both genders equally. MATERIALS AND ME...

ObjectiveTo test the hypothesis that telomere shortening and/or loss are risk factors for infertility.DesignRetrospective analysis of status in patients with infertility using conventional cytogenetic data collected prospectively.SettingAcademic centers.Patient(s)Cytogenetic slides cultured peripheral lymphocytes from 50 undergoing fertility treatment and 150 healthy donors, including 100 donor...

Twin and family studies establish the foundation for studying the genetic, environmental and cultural transmission effects for phenotypes. In this work, we make use of the well established statistical methods and theory for mixed models to assess cultural transmission in twin and family studies. Specifically, we address two critical yet poorly understood issues: the model identifiability in ass...

Correlations between relatives were determined for systolic and diastolic blood pressure. The correlations decrease as age differences between relatives increase in a Norwegian sample with 43,751 parent-offspring pairs, 19,140 pairs of siblings, and 169 pairs of twins. A simple biometric model specifying only age-specific genetic additive effects and environmental effects fitted well to correla...

The analysis of genetic and environmental contributions to preterm birth is not straightforward in family studies, as etiology could involve both maternal and fetal genes. Markov Chain Monte Carlo (MCMC) methods are presented as a flexible approach for defining user-specified covariance structures to handle multiple random effects and hierarchical dependencies inherent in children of twin (COT)...