The gene encoding human transmembrane secretory component (locus PIGR) is linked to D1S58 on chromosome 1.
The human transmembrane secretory component (SC or poly-Ig receptor, PIGR) is expressed basolaterally on glandular epithelial cells and is responsible for the external translocation of polymeric IgA and IgM. SC is hence a key molecule in antibody protection of mucosal surfaces. The human SC gene (locus PIGR) is located on chromosome 1 (1q31-q41). Here we present the first genetic linkage study of PIGR versus syntenic markers, including D1S58 and F13B, which have been previously regionalized to 1q31-q32 and 1q31-q32.1, respectively. We found that PIGR is closely linked to D1S58 (lods + 5.06 at theta max = 0.06, without sex difference). PIGR versus F13B showed + 1.46 at theta max = 0.25 for both sexes combined. A recombination of 0.06 between F13B and D1S58 (lods + 2.24) was in contrast to a previously published study giving theta max = 0.22 (lods + 3.9), the combined lods being 5.6 at theta max = 0.20. The progeny of a triply heterozygotic female indicated that PIGR is the flanking locus, therefore suggesting a cen-F13B-D1S58-PIGR-qter gene sequence on human chromosome 1. Only negative lod scores to RH, C8@, and PGM1 on 1p, and FY on proximal 1q, were found. Current combined Norwegian allele frequencies were estimated for PIGR to be A1 = 0.63, A2 = 0.37 (370 chromosomes), and for D1S58 to be A1 = 0.44, A2 = 0.56 (218 chromosomes).
Krajci
P
P
Laboratory for Immunohistochemistry and Immunopathology (LIIPAT), University of Oslo, National Hospital, Norway.
Gedde-Dahl
T
T
Høyheim
B
B
Rogde
S
S
Olaisen
B
B
Brandtzaeg
P
P
D002874:Chromosome Mapping; D002878:Chromosomes, Human, Pair 1; D005260:Female; D008040:Genetic Linkage; D006579:Heterozygote; D006801:Humans; D008126:Lod Score; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics*; D011971:Receptors, Immunologic; D012635:Secretory Component / Q000235:genetics*
D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; D012635:Secretory Component