Abstract 
A total of one hundred birds of commercial broiler (Ros 308) were selected 
randomly from a private flock at the age of 42 days. Samples of blood were collected
from each bird individually then birds were slaughtered. The genetic analyses was
performed in the laboratories of College of Science, University of Al-Nahrain, The aim
of extract DNA to identify genotypes (Genotype) gene CAPN1. The study aimed to find
the relationship of these genes (genetic markers) some important qualities of sacrifice
(slaughter weight, the weight of the main Alqtaaat, edible viscera weight, dressing
percentage, abdominal fat weight) in broilers under study Knowing repeating and repeat
genotypes and gene sequences to gene CAPN1 To improve the qualities  the most
important economic to broilers Meat. The results could be summarized as following:
gene were determined in the broilers of the current study depending on the bands that
got it from the electrophoresis of the individuals DNA using RFLP technique and
restricted enzyme with  (Bam H1) and the genotypes were determined according to the
size of the parts of the gene for gene CAPN1. Three types of genotypes for the CAPN1
gene were determined according to the flock size, where AA, AB and BB. The genotype
frequency of the mentioned genotypes were 0.25, 0.55 and 0.20 respectively and the
gene frequency was 52.5% A and 47.5% B. The genotype BB of the CAPN1 gene was
superior significantly (P<0.01) as compared with others genotypes concerning live body
weight, carcass weight, thigh weight, gizzard, and the ratio of upper thigh to the breast
width. The correlation coefficients between CAPN1 gene and each of the live body
weight, carcass weight and breast weight were significant and positive. The genotypes
BB for the CAPN1  are the distinct as they superior significantly (P<0.05) compared
with others genotypes due to the polymorphism of these gene, hence, we recommend
the using as genetic markers in the selection programs. The mutations were determined
in CAPN1 gene as a result of studying the sequences that indicate the occurrence of
mutations for the Substitution and deletion types (37.5%) while 25% did not show any
change in the broilers samples.