Jr. Bartlett et al., LINKAGE ANALYSIS OF ENDOGENOUS-VIRAL-ELEMENT-1, BLUE EGGSHELL, AND PEA COMB LOCI IN CHICKENS, The Journal of heredity, 87(1), 1996, pp. 67-70
Linkage analyses were conducted among endogenous viral element 1 (ev1)
, pea comb (P), and blue eggshell (O) loci, mapped to the short arm of
chromosome 1 in chickens. The F-1 males were produced from a cross be
tween pea comb Araucana males negative for ev1 and known to be homozyg
ous at the blue eggshell locus, and single comb White Leg horn females
positive for ev1 and laying white shelled eggs. Recombination data we
re based on birds from a test cross of three F-1 birds, each mated to
10 single combed, brown eggshell laying Rhode Island Red (RIR) hens, n
egative for ev1 integration. Birds were screened for ev1 by DNA amplif
ication using the polymerase chain reaction (PCR). Analyses of 207 pro
geny segregating for linkage between ev1 and P showed an estimated ave
rage map distance of 4.0 cM. Linkage analyses based on 44 progeny resu
lted in estimates of map distances of 1.8 and 4.1 cM between ev1 and O
and P and O loci, respectively. Based on these estimates, the order o
f these three loci on the short arm of chromosome 1 can be inferred to
be centromere, P, ev1, and O.