Related Experiment Video
Updated: Jul 8, 2026
10:59
Production of Apolipoprotein C-III Knockout Rabbits using Zinc Finger Nucleases
Published on: November 18, 2013
Apolipoprotein E polymorphism in sheep
K Tsunoda1, Y Yamamoto, Y Akiya
1Department of Legal Medicine, Showa University School of Medicine, Tokyo, Japan.
Biochemical Genetics
|May 7, 1999
Summary
Genetic polymorphism in sheep apolipoprotein E (APO E) was analyzed in European and Asian breeds. Seven codominant alleles (APOE1-APOE7) control APO E phenotypes, with distinct allele frequencies observed between the two sheep groups.
Area of Science:
- Animal Genetics
- Biochemistry
- Immunology
Background:
- Apolipoprotein E (APO E) plays a crucial role in lipid metabolism.
- Understanding APO E genetic polymorphism is vital for livestock breeding and health.
- Previous studies have focused on human APO E, with limited data on sheep.
Purpose of the Study:
- To investigate the genetic polymorphism of apolipoprotein E (APO E) in diverse sheep populations.
- To identify and characterize APO E variants and their allele frequencies in European and Asian sheep.
- To determine the inheritance pattern of APO E phenotypes in sheep.
Main Methods:
- Isoelectric focusing (IEF) of desialylated plasma proteins.
- Immunoblotting using anti-human APO E antibody for APO E detection.
- Analysis of family and population data to establish genetic control.
Main Results:
- Twenty APO E phenotypes were identified, resulting from combinations of seven detected variants (E1-E7).
- The APO E phenotypes are controlled by seven codominant alleles (APOE1-APOE7) at a single autosomal locus.
- Common alleles APOE4, APOE5, and APOE7 showed varying frequencies between European and Asian sheep groups.
Conclusions:
- The genetic polymorphism of sheep APO E is complex, involving multiple codominant alleles.
- Significant differences in APO E allele frequencies exist between European and Asian sheep populations.
- This study provides a foundation for further research into the functional and evolutionary significance of sheep APO E variants.
Related Concept Videos
01:39Epistasis
In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence phenotypes in a phenomenon called epistasis. For example, rabbit fur can be black or brown depending on whether the animal is homozygous dominant or heterozygous at a TYRP1 locus. However, if the rabbit is also homozygous recessive at a locus on the tyrosinase gene (TYR), it will have an unshaded coat that appears white, regardless of its TYRP1...
02:23RNA Editing
RNA editing is a post-transcriptional modification where a precursor mRNA (pre-mRNA) nucleotide sequence is changed by base insertion, deletion, or modification. The extent of RNA editing varies from a few hundred bases, in mitochondrial DNA of trypanosomes, to a just single base, in nuclear genes of mammals. Even a single base change in the pre-mRNA can convert a codon for one amino acid into the codon for another amino acid or a stop codon. This type of re-coding can significantly affect the...
01:05Single Nucleotide Polymorphisms-SNPs
A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...
01:09Epistasis Analysis
Although Mendel chose seven unrelated traits in peas to study gene segregation, most traits involve multiple gene interactions that create a spectrum of phenotypes. When the interaction of various genes or alleles at different locations influences a phenotype, this is called epistasis. Epistasis often involves one gene masking or interfering with the expression of another (antagonistic epistasis). Epistasis often occurs when different genes are part of the same biochemical pathway. The...
01:16Pharmacogenetics of Drug Transporters: P-Glycoprotein and Solute Carrier Transporters
The pharmacogenetics of drug transporters is increasingly recognized as a critical factor influencing interindividual variability in drug absorption, distribution, and elimination. These membrane-bound proteins regulate drugs' movement across cellular barriers by actively pumping them out (efflux) or facilitating their uptake (influx). Among the major transporter families, ATP-binding cassette (ABC) and solute carrier (SLC) transporters play particularly prominent roles. Genetic polymorphisms...
01:11Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Genetic polymorphisms in drug targets have emerged as critical determinants of interindividual variability in drug response and toxicity. Pharmacogenomic investigations increasingly focus on identifying these variations to personalize and optimize therapeutic interventions. A drug target may be a receptor, enzyme, or signaling protein involved in pharmacologic responses or disease-related pathways. While early pharmacogenetic studies focused primarily on drug metabolism, current research...