Bovine αs1-casein F (αs1-CN F)
was found in a genetic resource of
Deutsches Schwarzbuntes Niederungsrind cows at a frequency of 0·009.
Biochemical
characterization of this new variant was obtained by automated sequencing
of
reversed-phase HPLC-separated tryptic peptides of αs1-CN
F
and αs1-CN B. αs1-CN F was found to be
a
subtype of αs1-CN B with a single amino acid substitution
(SerP/Leu) in position 66. DNA sequencing revealed a C/T transition
in position
8418 of the gene. Sequence-specific primers were designed to perform an
allele-specific
polymerase chain reaction for detection of αs1CnF.
Typing of artificial insemination sperm samples included in the genetic
resource
sperm pool identified one sire heterozygous for αs1CnF.