Guidelines on retention of pathology records and materials (Version 2/2022).

No abstract available.

De novo interstitial deletion of 1q32.2-q32.3 including the entire IRF6 gene in a patient with oral cleft and other dysmorphic features.

BACKGROUND: Microdeletion of the Van der Woude syndrome (VWS) critical region is a relatively rare event, and only a few cases have been reported in the medical literature. The extent of the deletion and the genotype-phenotype correlation are 2 crucial issues. METHODS AND RESULTS: During analysis of the VWS critical region in 95 families with an isolated cleft of the lip with or without cleft palate, we found a de novo interstitial deletion of 1q32.2-q32.3 in a patient with cleft lip and other dysmorphic features. The present case showed new proximal and distal end breakpoints compared to those previously reported. The results of a short tandem repeat analysis was confirmed using high resolution array-based comparative genomic hybridization and showed an interstitial deletion of approximately 2.98 Mb which involved 25 genes, including the entire IRF6 gene. Direct sequencing of the non-deleted allele of the IRF6 gene did not show any mutation, which supports a haploinsufficiency mechanism of the IRF6 gene in the development of the oral cleft. CONCLUSION: The present report adds to the collective knowledge that oral cleft is a major clinical feature of the 1q32.2-q32.3 deletion.

Familial complex chromosomal rearrangement in a dysmorphic child with global developmental delay.

We report the unusual case of a dysmorphic child with global developmental delay secondary to a familial complex chromosomal rearrangement (CCR). His chromosomal analysis using G-banding and dual colour fluorescence in situ hybridisation with whole chromosome paint revealed a supernumerary marker chromosome as a result of malsegregation of a familial CCR involving chromosomes 7, 12 and 14. The balanced form of this familial CCR was also carried by the patient's mother and maternal grandmother, both of whom had a history of recurrent spontaneous abortions, as well as his maternal uncle, who was infertile. To the best of our knowledge, this is the first reported case of familial CCR involving chromosomes 7, 12 and 14. This case also highlights the importance of chromosomal analysis in children with dysmorphism and developmental delay as well as in adults who suffer from recurrent spontaneous abortions or infertility.

MECP2 mutations in Malaysian Rett syndrome patients.

INTRODUCTION: Rett syndrome (RS) is a severe neurodevelopmental disorder characterised by normal neurological development followed by progressive developmental regression. The X-linked dominant inheritance of RS has been mapped to the gene that encodes the methyl-CpG-binding protein-2 (MECP2) at Xq28. In the present study, denaturing high-performance liquid chromatography (DHPLC) was used to detect mutations in the MECP2 gene in 20 Malaysian RS patients. METHODS: Polymerase chain reaction (PCR) was carried out to amplify the MECP2 coding exons 2, 3, and 4 in a total of eight reactions (exons 2, 3a, 3b, 4a, 4b, 4c, 4d and 4e). Subsequently, PCR products were analysed by DHPLC. RESULTS: Mutations in the MECP2 gene were detected in 13 of the 20 (65 percent) RS patients. 11 patients had mutations in exons 3b and 4a and six patients had mutations in exon 4c. These mutations were mainly concentrated in the methyl-CpG-binding domain and the transcriptional-repression domain. CONCLUSION: Through the use of post-PCR high-performance liquid chromatography, 65 percent of 20 RS patients were found to have mutation(s) in the MECP2.