The importance of the genetic factor in the aetiology of premature ovarian failure (POF) is emphasized by the high percentage of familial cases and X chromosome abnormalities account for 10% of chromosomal aberrations. In this study, we report the detailed analysis of 4 chromosomal abnormalities involving the X chromosome and associated with POF that were detected during a screening of 269 affected women. Conventional and molecular cytogenetics were valuable tools for locating the breakpoint regions and thus the following karyotypes were defined: 46,X,der(X)t(X;19)(p21.1;q13.42)mat, 46,X,t(X;2)(q21.33;q14.3)dn, 46,X,der(X)t(X;Y)(q26.2;q11.223)mat and 46,X,t(X;13)(q13.3;q31)dn. A bioinformatic analysis of the breakpoint regions identified putative candidate genes for ovarian failure near the breakpoint regions on the X chromosome or on autosomes that were involved in the translocation event. HS6ST1, HS6ST2 and MATER genes were identified and their functions and a literature review revealed an interesting connection to the POF phenotype. Moreover, the 19q13.32 locus is associated with the age of onset of the natural menopause. These results support the position effect of the breakpoint on flanking genes, and cytogenetic techniques, in combination with bioinformatic analysis, may help to improve what is known about this puzzling disorder and its diagnostic potential.
This paper reports a new hemoglobin variant which was identified while investigating the cause of a mild erythrocytosis. The abnormal beta-globin chain was detected by reversed phase chromatography. Mutation mapping of the beta-globin gene by polymerase chain reaction and denaturing gradient gel electrophoresis followed by sequence analysis revealed a C-->A transversion at codon 38, predicting a Thr-->Asn substitution. Tryptic peptide mapping by liquid chromatography electrospray mass spectrometry, followed by conventional Edman peptide sequence analysis, confirmed the predicted amino acid substitution. In contrast to the only other known mutation at codon 38, Hb Hazebrouck (Thr-->Pro), this hemoglobin is stable and shows elevated oxygen affinity.
We have observed a male and a female, sibs of non-consanguineous parents, affected by severe myopia with characteristic retinal defects and Dandy-Walker variant. The peculiarity of the retinopathy consists of pathological myopia with anomalous vitreal fenestrated membranes in the retinal periphery. We suppose that these associations may configure a new genetic syndrome.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.