Abstract
A female proband (one of fraternal twins) presented for molecular analysis of Fragile X syndrome. Southern Blot analysis indicated a normal female methylation profile at the FMR-1 gene, but atypical intensities of the non-methylated and methylated alleles, suggesting reduced dosage of the methylated locus. Cytogenetic analysis of the patient's lymphoblasts showed a mosaic chromosome profile in which half the cells exhibited a 46,XX karyotype and the remaining cells were 46,XY. Subsequent analysis of buccal cells of the patient showed predominantly a 46,XX karyotype. These data were taken to suggest anastomosis and haematopoietic stem cell exchange (“haematopoietic chimerism”) with the proband's male twin early in development. To confirm this suggestion lymphoblast and buccal DNA from each twin were subjected to analysis using the Applied Biosystems Identifiler kit. The profile of each twin exhibited multiple alleles at most autosomal loci using DNA extracted from lymphoblasts, but one–two alleles dominate at loci using buccal cell DNA, thereby confirming haematopoietic chimerism.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Forensic Science International: Genetics Supplement Series
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
