Veterinary Genetics

• Genetics is a fraction of biology that studies heredity
• Genetics is the center of all biology because gene activity underlies all biological processes
• Genetics studies biological properties that are transmitted from parents to offspring, including genes, the molecular nature of these genes, how these genes are transmitted from generation to generation, and the study of how these genes are expressed and how their activity is regulated
• An understanding of gene structure, activity and regulation helps to understand how these genes control all biological processes (from cell structure to reproduction)
• Veterinary Genetics


  Concerning the heredity of characters (health and production related) associated with animal species, both livestock and other animal species
• Animal Breeding


  The application of principles of genetics in the breeding and selection of animals for the purposes of production of food, fiber and other products, recreation and other economic activities
• Classic Genetics


  Studies and discoveries previous to the Central Dogma of genetics proposed by Beadle and Tatum in 1941, encompassing mainly transmission genetics
• Modern Genetics


  Studies and discoveries after 1941, mainly Molecular genetics
• Subdisciplines of Genetics


  • Transmission Genetics
  • Molecular Genetics
  • Quantitative Genetics
  • Population Genetics
• Transmission Genetics


  Classic genetics - how genes are transmitted from generation to generation and how they recombine
• Molecular Genetics


  Molecular structure and function of genes, analyzing the sequence of the nitrogen bases in a gene and how it may change its expression
• Quantitative Genetics


  Studies heredity of a trait in a large group of individuals, but the individual trait is codified by many genes simultaneously
• Population Genetics


  Studies heredity of one or a few genes in a large group of individuals (population)
• Tools used in Genetic Research

  • Classic techniques of breeding such as crosses, backcrosses and testcrossing
  • Microscopic techniques, such as SEM, TEM, and others
  • Molecular techniques such as DNA sequencing, PCR, cloning, etc.
  • Use of genetic model organisms
  • Construction of Genetic maps
  • Genetic Databases
• Research in genetics has been progressing very well since the term genetics was introduced in the early 20th century
• The scope of research has advanced from traditional selective breeding of plants and animals to the modern genetics of DNA sequencing, genetic manipulation and now come to the era of genome editing
• The 12th Malaysia International Genetics Congress (MiGC12) was held on the 25-27th September 2017 in Bangi-Putrajaya Hotel, Bangi, Selangor, Malaysia, with the theme "Soaring Beyond Frontiers of Genetics", reflecting the ever increasing knowledge and understanding on the effect of genes in every sphere of life
• The highlight of MiGC12 was genome editing specifically focusing on the CRISPR system, and it covered genetic topics for plants, human, animal and microbes
• The biological information fundamental to life is encoded in the molecule of DNA
• DNA (deoxyribonucleic acid) is the genetic material in all prokaryotes, eukaryotes and some viruses, while other viruses have RNA
• The molecule of DNA is made of two strands (chains), and each strand is a chain of nucleotides, each consisting of a phosphate group, a pentose (5C sugar) and a nitrogen base (A, G, C, T)
• The arrangement of the nucleotides in the chain forms a double helix
• Genes (Mendel called factors)


  Specific sequences of nucleotides
• Genome


  The full sequence of the DNA or all the genes
• In the cell, the genetic material (DNA) is organized in structures called chromosomes
• Many prokaryotes (not all) have a single, usually circular chromosome made of DNA only, while in eukaryotes, the DNA is located in the nucleus forming linear chromosomes, each consisting of a single DNA molecule complexed with histone proteins
• Chromosome


  A carrier of genetic information
• Chromosome


  • Chromatid - one of the two identical parts of the chromosome
  • Centromere - the point where the two chromatids touch, and where the spindle fibers attach and a kinetochore is formed
  • Short arm
  • Long arm
• Centromere


  A constricted region of a chromosome that separates it into a short arm (p) and a long arm (q)
• Gene


  A segment of the chromosome that codes for a protein, a region of DNA that controls a hereditary characteristic, carrying biological information
• DNA is a whole genetic material but Genes are functional region of these DNA molecules
• Gene


  The fundamental physical and functional unit of heredity that is passed on from parents to progenies, an ordered sequence of nucleotides located in a specific location (locus) on a particular chromosome that encodes a specific functional product (the gene product e.g., a protein, mRNA molecule), including regions involved in regulation of expression and regions that code for a specific functional product
• Genes can be as short as 1000 base pairs or as long as several hundred thousand base pairs, and it can even be carried by more than one chromosome
• Gene


  Not a single bead (DNA segment with exons & introns), may not produce a single gene product, may produce many gene products of proteins and enzymes, "A locatable region of genomic sequence, corresponding to a unit of inheritance, which is associated with regulatory regions and/or other functional sequence regions"
• Exons


  The DNA bases that are transcribed into mRNA and eventually code for amino acids in the proteins (Coding DNA)
• Introns


  DNA bases, which are found between exons, but are not transcribed (Interrupting DNA)
• Genes which contain introns are known as interrupted genes
• Genetic Marker


  Any alteration in a sequence of nucleic acids or other genetic trait that can be readily detected and used to identify individuals, populations, or species or to identify genes involved in inherited disease, including regions of DNA (genes) or some segments of DNA with no known coding function but whose pattern of inheritance can be determined, such as restriction fragment length polymorphism (RFLP), simple sequence length polymorphisms (SSLPs), single nucleotide polymorphism (SNPs), Insertions/deletions (indels)
• A gene can be defined as a region of DNA that controls a hereditary characteristic
• Genes


  May not produce a single gene product, may produce many gene products of proteins and enzymes