1/3. Molecular cloning of translocation breakpoints in a case of constitutional translocation t(11;22)(q23;q11) and preparation of probes for preimplantation genetic diagnosis.in vitro fertilization (IVF) centres with preimplantation genetic diagnosis (PGD) programmes are often confronted with the problem of identifying chromosomal abnormalities in interphase cells biopsied from preimplantation embryos of carriers of a reciprocal translocation. The present authors have developed a dna testing based approach to analyse embryos from translocation carriers, and this report describes breakpoint-spanning probes to detect abnormalities in cases of the most common human translocation (i.e. the t(11;22)(q23;q11)). Screening a yeast artificial chromosome (YAC) library for probes covering the respective breakpoint regions in the patient lead to probes for the breakpoint on chromosome 11q23. The physically mapped YAC and bacterial artificial chromosome (BAC) clones from chromosome 22 were then integrated with the cytogenetic map, which allowed localization of the breakpoint on chromosome 22q11 to an interval of less than 84 kb between markers D22S184 and KI457 and to prepare probes suitable for interphase cell analysis. In summary, breakpoint localization could be accomplished in about 4 weeks with additional time needed to optimize probes for use in PGD.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
2/3. infertility. A psychiatrist's perspective.This paper discusses issues relevant to psychiatrists working in a reproductive biology unit: 1. The couple's anxiety. 2. The question of whether psychological conflict can cause infertility. 3. Dealing with the outcome of the workup. 4. Donor insemination. The anxiety of couples applying for an infertility workup can usually be countered by supportive and educative measures. More problematic sources of anxiety that require psychiatric consultation are: 1) fear that the workup may shatter a myth that explains the infertility, a myth reinforced by unconscious conflicts; 2) An untenable wish that having a child will repair problems in the marriage or in the sense of relief. The psychiatrist is often asked whether psychological conflicts can cause infertility. The most understandable manner in which they do is by their effect on sexual performance. Where there is no sexual performance problem, psychotherapy can be offered if one or both partners experiences psychological pain, but with the understanding that therapy cannot be expected to cure the infertility. Psychiatric consultation at the end of the workup is indicated 1) where irreversible infertility is discovered and mourning is excessive, 2) where a myth to explain the infertility has been shattered, 3) to reassess sexual performance and to deal with the uncertainty, where no physical cause has been discovered. Donor insemination (AID) is fraught with legal and ethical problems. There are no criteria for selecting donors or recipient families, and there is concern that AID may lead to genetic engineering. The psychological effects of AID are uncertain. A study at our clinic suggests that the pursuit of AID involves a two-stage process: first, dealing with the outcome of the infertility workup and second, confronting AID itself; and that the secrecy that surrounds AID obstructs resolution of conflict.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
3/3. Conventional and molecular cytogenetic identification of a variant klinefelter syndrome patient with a deleted x chromosome.We report on the case of a 34-year-old patient with the klinefelter syndrome and an unusual cytogenetic finding of a deletion involving the short arm of the x chromosome. This was confirmed with fluorescent in situ hybridization (FISH) using an x chromosome-specific whole chromosome painting probe. The patient presented with infertility. The only abnormal physical findings were atrophic testes with azoospermia and elevated levels of follicle-stimulating hormone and luteinizing hormone. This case represents a relatively mild manifestation of the klinefelter syndrome. Previous reported cases were often associated with more severe phenotypes such as variable degrees of mental retardation and facial dysmorphism, hypothesized as due to the failure of X inactivation. The X inactivation center, located on Xq13, is presumably intact in our patient, who had a deletion involving only the short arm. The mild phenotype observed in our patient was found to be consistent with the conventional and molecular cytogenetic findings.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |