The primary immunodeficiency disorders reflect abnormalities in the development and maturation of cells of the immune system. These defects result in an increased susceptibility to infection; recurrent pyogenic infections occur with defects of humoral immunity, and opportunistic infections with defects of cell-mediated immunity. These two broad categories of illness correspond roughly to defects in the two principal types of immunocompetent cells, B lymphocytes and T lymphocytes. Defective development of B cells results in abnormalities in humoral immunity, whereas defects in the development of T cells cause problems with cellular immunity. When pathogens are taken up by macrophages or dendritic cells, . . .

The Primary Immunodeficiencies

Classical antibody deficiency syndromes, such as sex-linked aggammaglobulinemia, are rare and relatively homogeneous in presentation. In the present investigation an unselected group of 3,213 individuals from a community health study was examined in an attempt to estimate the prevalence of the commoner and largely unclassified examples of immunoglobulin deficiencies defined by the lower 2.5 per cent of the population. The prevalence of selective IgA deficiency (an isolated absence of IgA) was 0.097 per cent and that for selective IgM deficiency was 0.03 per cent. No isolated absence of IgG was found. In addition to these deficiency syndromes, concentrations of each of the immunoglobulins were found to be highly correlated to each other.

https://www.jacionline.org/article/S0091-6749(75)80006-6/pdf

Human serum immunoglobulin concentrations: prevalence of immunoglobulin deficiencies

Twenty-six patients with deletions of 18q were analyzed at the clinical and molecular levels in an attempt to delineate regions of chromosome 18 important to the 18q- syndrome phenotype. Molecular cytogenetic analysis was carried out using fluorescence in situ hybridization (FISH), and deletions ranging from 18q21.1-qter to 18q22.3-qter were detected. The parental origin of the deletions was determined by the analysis of inheritance of microsatellite markers. No correlation between size, parental origin, or severity of the resulting phenotype was found. The results suggest that a critical region for 18q- syndrome lies in the most distal portion of 18q and that it confers susceptibility for the various clinical manifestations of the 18q- syndrome when present in one copy.

Analysis of clinical variation seen in patients with 18q terminal deletions.

Autoimmune hemolytic anemia: Natural history and viral-immunologic interactions in childhood

Clinical and chromosomal studies of the 18q-syndrome

IN CONTRAST to the X chromosome, little is known about the autosomal loci for various genetic traits. Recently Gerald et al1 and Bloom et al 2 have presented suggestive evidence that the controlling formation of locus the α-chain of haptoglobin is situated on one end of a No. 13 chromosome. We have studied two patients with chromosome defects and dysgammaglobulinemia. One had a No. 18 ring chromosome, which is formed by breakage in both arms with reunion of the broken ends and loss of a variable amount of material distal to each break. The other had a partial deletion of the long arm of the same chromosome. In both patients IgA was not detectable, and, in one, the level of IgG was very low. These patients are the first recognized examples of dysgammaglobulinemia associated with a chromosomal deletion. Report of Cases Case 1.—A 3-year-old white boy was first admitted to

Murray Feingold

Papers

IgA Deficiency Associated With Partial Deletion of Chromosome 18

IgA AND PARTIAL DELETIONS OF CHROMOSOME 18