Severe combined immune deficiency due to a homozygous 3.2-kb deletion spanning the promoter and first exon of the adenosine deaminase gene.

AUTOR(ES)

Berkvens, T M

RESUMO

We have investigated the structural gene for adenosine deaminase (ADA) in a female infant with ADA deficiency associated severe combined immune deficiency (ADA-SCID) disease and her family by DNA restriction-fragment-length analysis. In this family a new ADA-specific restriction-fragment-length variant was detected, which involves a 3.2-kb deletion spanning the ADA promoter as well as the first exon. It was found that the patient, who was born to a consanguineous couple, was homozygous and both her parents and her brother were heterozygous for the deletion. No ADA-specific mRNA could be detected by hybridization in fibroblasts derived from this patient. Thus the patient was established to be homozygous for a true null ADA allele. In the light of the apparently normal development of most tissues except the lymphoid tissue the above finding directly questions the classification of ADA as a 'housekeeping' enzyme.

Documentos Relacionados

• Adenosine deaminase (ADA) deficiency due to deletion of the ADA gene promoter and first exon by homologous recombination between two Alu elements.
• Homozygous hereditary C3 deficiency due to a partial gene deletion.
• T lymphocyte ontogeny in adenosine deaminase-deficient severe combined immune deficiency after treatment with polyethylene glycol-modified adenosine deaminase.
• Immune deficiency due to adenosine deaminase and purine nucleoside phosphorylase deficiency: a simple diagnostic test.
• Adenosine deaminase (ADA) deficiency in cells derived from humans with severe combined immunodeficiency is due to an aberration of the ADA protein.