Severe combined immunodeficiency, autosomal recessive, T cells negative, B cells positive, NK cells positive ) - Genes PTPRC and IL7R genes
Severe combined immunodeficiency (SCID) encompasses a genetically and clinically heterogeneous group of disorders with an immune cell function and humoral defective. SCID can be divided into two main classes: those with B lymphocytes (SCID, B +) and those without B cells (SCID, B-). The presence or absence of NK cells varies within these groups. Patients with SCID suffer in childhood recurrent and persistent infections by opportunistic organisms, including Candida albicans, Pneumocystis jirovecii and cytomegalovirus, among many others. The common feature of all types of SCID is the absence of T cell immunity mediated cell due to a defect in T - cell development Untreated patients generally die in the first year of life.
People affected with SCID T-, B +, NK +, may have fever, rash, hepatosplenomegaly, lymphadenopathy, pneumonitis, pancytopenia, growth failure, viral infections and severe and persistent fúngicass.
This process is due to mutations in genes PTPRC and IL7R.
The IL7R gene, located on the short arm of chromosome 5 (5p13), encodes a receptor for interleukin-7, a 25 kD glycoprotein that participates in the regulation of lymphopoiesis. This ligand-receptor complex is essential for the normal development of T cells
Meanwhile, the PTPRC gene, located on the long arm of chromosome 1 (1q31-q32), encoding a protein family member of the protein tyrosine phosphatase (PTP). PTPs are signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitosis, and oncogenic transformation. This PTP contains an extracellular domain, a single transmembrane segment and two tandem intracytoplasmic catalytic domains, and thus is considered a receptor. This PTP is an essential regulator of antigen receptor signaling in T and B cell operates through direct interaction with components of the antigen receptor complexes, or by activating various Src family kinases required for receptor signaling antigen. This PTP also suppresses JAK kinases, and thus functions as a regulator of cytokine receptor signaling.
This disease is inherited in an autosomal recessive pattern, that is, both copies of the gene in every cell must have mutations for alteration is expressed. The parents of an individual with an autosomal recessive disease have a copy of the mutated gene, but usually show no signs and symptoms of the disease.
Tests performed in IVAMI: in IVAMI perform the detection of mutations associated with severe combined immunodeficiency, autosomal recessive, negative T cells, positive B cells, positive NK cells through the complete PCR amplification of the exons of PTPRC and IL7R genes, respectively and subsequent sequencing.
Recommended samples: EDTA blood drawn for blood separation ucocitos him or impregnated card with dried blood sample (IVAMI can mail the card to deposit the blood sample).