Læknablaðið : fylgirit - 01.06.1982, Blaðsíða 51

38
SELECTIVE SERUM Ig A DEFICIENCY IN ICELANDERS:
FREQUENCY, FAMILY STUDIES AND Ig LEVELS
J. Olfarsson, S. Guömundsson, B. Birgisdóttir,
J.M. Kjeld 1) and Ó. Jensson.
The Blood Bank and Dept. of Clinical Biochemistry 1)
University Hospital of Iceland.
From 1974-1979 over 15.000 Icelanders (6.1%
of the population), mostly healthy male blood
donors, were screened for selective Ig A deficiency
(SlgAD ) by immunodiffusion (Outcherlony). Fre-
quency of SlgAD in blood donors was 1/633 (0.158%).
All in all, 35, individuals were classified as Ig A
deficient by screening population and families.
Immunoglobulins A, G, M and E were measured in 119
members in families of 18 propositi found by
screening.
Pedigree studies suggested both autosomal
dominant and recessive modes of inheritance of
SlgAD. A trend of clustering of similar Ig G and
Ig E levels (within norraal ranges) was apparent in
several families. An increased Ig G level in family
members with SlgAD was significantly more frequent
(p"^ 0.001) than in members with normal levels of
Ig A. Ig G levels were found to be high in 12 (44%)
and normal in 15 of the 27 subjects with low or
deficient Ig A who were healthy when examined, and
only 5 gave a history of allergy or recurrent resp-
iratory infections.
It is suggested that immun response (IR)
genes could be influential in causing the difference
in Ig levels among the SlgAD family members.