Related Experiment Video
Updated: Nov 18, 2025

Use of Bisection to Reduce Mitochondrial DNA in the Bovine Oocyte
Published on: July 6, 2022
A 44-kb deleted-type copy number variation is associated with decreasing complement component activity and calf
Shinji Sasaki1,2, Youko Miki3, Takayuki Ibi4
1University of the Ryukyus, Faculty of Agriculture, 1 Senbaru, Nishihara, Nakagami-gun, Okinawa, 903-0213, Japan. sasaki12@agr.u-ryukyu.ac.jp.
Background:
Calf mortality generally occurs in calves prior to weaning, which is a serious problem in cattle breeding. Several causative variants of monogenic Mendelian disorders in calf mortality have been identified, whereas genetic factors affecting the susceptibility of calves to death are not well known. To identify variants associated with calf mortality in Japanese Black cattle, we evaluated calf mortality as a categorical trait with a threshold model and performed a genome-wide copy number variation (CNV) association study on calf mortality.
Results:
We identified a 44-kb deleted-type CNV ranging from 103,317,687 to 103,361,802 bp on chromosome 5, which was associated with the mortality of 1-180-day-old calves. The CNV harbored C1RL, a pseudogene, and an IncRNA localized in the C1R and C1S gene cluster, which is a component of the classical complement activation pathway for immune complexes for infectious pathogens. The average complement activity in CNVR_221 homozygotes at postnatal day 7 was significantly lower than that of wild-type animals and heterozygotes. The frequency of the risk allele in dead calves suffering from diarrhea and pneumonia and in healthy cows was 0.35 and 0.28, respectively (odds ratio = 2.2, P = 0.016), suggesting that CNVR_221 was associated with the mortality of Japanese Black calves suffering from an infectious disease.
Conclusions:
This study identified a deleted-type CNV associated with the mortality of 1-180-day-old calves. The complement activity in CNVR_221 homozygotes was significantly lower than that in heterozygotes and wild type animals. The frequency of the risk allele was higher in dead calves suffering from an infectious disease than in healthy cows. These results suggest that the existence of CNVR_221 in calves could be attributed to a reduction in complement activity, which in turn leads to susceptibility to infections. Thus, the risk allele could serve as a useful marker to reduce the mortality of infected Japanese Black calves.
More Related Videos
09:32An Array-based Comparative Genomic Hybridization Platform for Efficient Detection of Copy Number Variations in Fast Neutron-induced Medicago truncatula Mutants
Published on: November 8, 2017
07:58qKAT: Quantitative Semi-automated Typing of Killer-cell Immunoglobulin-like Receptor Genes
Published on: March 6, 2019
Related Concept Videos
Comparing Copy Number Variations and SNPs
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Lethal Alleles
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
Animal Mitochondrial Genetics
Incomplete Dominance
Complementation Tests
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...