Wrong! Everybody has the "O-gene."
Genes are expressed as polypeptides or proteins. The A and B
antigens are NOT proteins but rather glycolipids found on the
membranes of most human cells. The proteins produced by "A and B
genes" are enzymes that catalyze the addition of specific sugars
(either N-acetylgalactosamine or D-galactose) to a glycolipid
consisting of L-fucose: D-galactose: N-acetylglucosamine:
D-galactose: N-acetylgalactosamine:lipid. The five sugar glycolipid
is sometimes called the 'H-antigen" although it is actually
non-antigenic. The A or B antigens are formed by the addition of
either N-acetylgalactosamine or D-galactose to the H-antigen.
The so called "O gene" produces the glycosylating enzyme (or enzymes)
producing the "H-antigen." There are "A-genes, B-genes, and "O
genes" as well as an A-antigen, a B-antigen, and a "H-antigen" and
they are apparently inherited in a Mendelian fashion.
>In human blood groups the AB blood type has a gene for type A blood inherited
>from one parent and a gene B inherited by the other parent, so you see there
>are no O genes in blood group AB therefore a baby with blood type O can not
Richard L. Hall, Ph.D.
Comparative Animal Physiologist
University of the Virgin Islands
2 John Brewers Bay
St. Thomas, U.S.V.I. 00802
rhall at uvi.edu
"Live life on the edge...the view is always better" rlh
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