Congenic Strain

Congenic strains are special type of strains where a specific and defined part of the genome from one inbred strain (strain A) is introgressed on the genetic background of second inbred strain (strain B). The congenic strain is an inbred strain, so it is homozygous throughout the whole genome, the only difference between strain B and congenic strain B.A# (where # is a specific number of the chromosome) is just the "differential" segment of chromosome #. If strain B and congenic strain B.A# differ in any phenotype (body weight, glycemia, or sensitivity to teratogen), it can be deducted that within the differential segment there is a gene or there are genes responsible for genetic determination of followed trait. Special types of congenic strains include consomic strains and conplastic strains.