Immunological and molecular study in children with combined immunodeficiency.

Summary: Background. Severe combined immunodeficiency (SCID) is a form of immunodeficiencies (PID), caused by molecular defects. These defects can restrict the development and function of lymphocytes. Early diagnosis and treatment of SCID can lead to disease-free survival. Objective. This study aims to investigate some of the possible underlying genetic defects in a group of Egyptian infants and children with clinical and immunological profiles suggestive of SCID. Methods. This study included eighty patients who showed clinical warning signs of immunodeficiency. Subjects were thoroughly examined clinically. Laboratory evaluation included immunoglobulins serum levels and flow cytometric assessment of immune cells. This testing showed an altered immune profile in thirty patients. They had decreased T and/or B lymphocytes or natural killer cells. DNA extraction was done for those cases. The coding regions of the RAG1 gene and RAG2 gene was investigated for hot spot mutations by sequencing technique guided by the patient clinical evaluation, inheritance pattern, immunophenotyping by flow cytometric analysis of lymphocyte subsets, and serum immunoglobulins level detection. Results. Results showed novel and previously reported variants (mutation, polymorphism), they were found in 18 cases which include variants in the RAG1 gene (E880K, A960A, H249R, S913R, K820R, V782G), and variants in the RAG2 gene (P501T, L514M, rs10836573, cDNA.2129A>T). Conclusions. To evaluate SCID patients completely; mutation gene analysis is highly required and recommended.

Detection and putative effect of GATA4 gene variants in patients with congenital cardiac septal defects.

The zinc finger transcription factor GATA4, located on chromosome 8p23.1-p22, has been implicated as a critical regulator of cardiac development during embryogenesis. Mutations of GATA4 appear to be responsible for some cardiac septal defects. The aim of this work was to screen for mutations in the GATA4 gene in sample of Egyptian patients affected by isolated and non-isolated cardiac septal defects. We examined 20 patients with atrial septal defect (ASD), ventricle septal defect (VSD), atrioventricular septal defects (AVSD) and A-V canal disturbance defect and compared with examined 10 unaffected individuals as normal control. The patients were referred from Congenital Heart Disease Clinic of the Clinical Genetics department at the National Research Centre. All patients were subjected to clinical evaluation, echocardiography and karyotyping. Genomic DNA was extracted from all cases and subjected to PCR followed by direct sequencing. The predicted effect of variants was done by a variety of proper prediction tools. We detected six variants in GATA4 gene, two of them are novel variants. Predicted functional analysis of the relevant variants was performed by In silico analysis. Further confirmatory studies on familial segregation and in vitro / in vivo functional analysis are recommended to support our results.