A comprehensive linkage map of the chicken genome has been developed b
y segregation analysis of 430 microsatellite markers within a cross be
tween two extreme broiler lines. The population used to construct the
linkage map consists of 10 families with a total of 458 F2 individuals
, The number of informative meioses per marker varied from 100 to 900
with an average of 400. The markers were placed into 27 autosomal link
age groups and a Z-chromosome-specific linkage group, In addition, 6 m
arkers were unlinked, 1 of which was Z chromosome specific, The covera
ge within linkage groups is 3062 cM. Although, as in other species, th
e genetic map of the heterogametic sex (female) is shorter than the ge
netic map of the homogametic sex (male), the overall difference in len
gth is small (1.15%), Forty-five of the markers represent identified g
enes or ESTs. Database homology searches with the anonymous markers re
sulted in the identification of a further 9 genes, bringing the total
number of genes/ESTs on the current map to 54. The mapping of these ge
nes led to the identification of two new regions of conserved synteny
between human and chicken and confirmed other previously identified re
gions of conserved synteny between human and chicken. The linkage map
has 210 markers in common with the linkage maps based on the East Lans
ing and Compton reference populations, and most of the corresponding l
inkage groups in the different maps can be readily aligned. (C) 1998 A
cademic Press.