(01) Introduction Flashcards
Evolutionary and systematic biology are studies of what?
Long-term applications of genome replication and the study of the diversity of life resulting from the modulation of replication by environmental factors
What are morphology, biochemistry, and physiology studies of?
The structural and functional consequences of the activites of the genetic materal at all levels, from molecular and cellular to organismal
Ecology is the study of what?
interaction of genetically programmed individuals and populations with the environment
Developmental biology is the study of what?
Those aspects of replication that occur within the life span of individual organisms
Immunology is the study of what?
The immune response of a host genome
Two principles of animal breeding
- individual traits can be passed on to next generation
- individual traits can be present but not visible
What happens in porcine stress syndrome (malignant hyperthermia)? What is the desired aim of this breeding?
What homozygous gene caused the muscle damage?
- too much calcium released during stress, causes muscles to tense up providing bad meat quality
- lean, heavy muscling
- RYR1 (recessive - so heterozygous are fine)
What is a locus?
a unique location on a chromosome
What is a gene?
unit of genetic information that controls a trait
What is an allele? What may they have?
- a different form of a gene or locus
- a known underlying molecular component such as a single nucleotide mutation or duplication/deletion
What are other names for Nucleotide mutations? How often do they occur?
What are the two types? What causes transitions? Which is more common? What is a transversion? What is a transversion?
- single nucleotide polymorphisms, SNPs
- 1/1000 bp in human genome
- Transitions and Transversions
- oxidative deamination and non-canonical (unusual) base pairing
- Transitions (2x more frequent)
- purine > purine or pyrimidine > pyrimidine
- pyrimidine > purine or vice versa
What is a silent mutation?
- (synonymous) alter codon, but no change in amino acid (cause Leucine equals TTA, TTG, CTT, etc
What is a mis-sense mutation?
- (non-synonymous) change the AA
What is a non-sense mutation?
- premature stop codon (TTA to TAA)
What is a frameshift mutation?
- when there is an insertion/deletion that shifts the whole thing
Where can non-coding mutations occur?
- splice site mutations, promoter, “control regions”
What is a genotype?
- the combination of alleles present in an individual
What is a phenotype?
- the characteristics of the trait that are expressed (a product of the genotype in the environment)
What is a copy-number variation (CNV)? What are they associated with? What size are they? CNV’s comprise at least 3X the total nucleotide content of what?
- variation in the DNA of a genome that results in individuals having an abnormal number of copies of one or more regions of the genome
- diseases
- thousands to millions of DNA base pairs
- SNPs
Why do chimps have two diploid copies of salivary amylase (AMY1) but humans have 6 to 15?
- adaptation to high starch diet
What is haploid?
having one copy of each gene
What is diploid?
- having two copies of each gene
What is a polymorphism? homozygote? heterozygote?
- presence of multiple alleles at a gene
- individual with 2 copies of the same allele
- individual with one copy each of two different alleles
Polyploid / euploid? aneuploid?
- multiple of monoploid number
- abnormal number (ie down syndrome, one extra chromosome)
What is variable expressivity? What does it refer to?
- variations in a phenotype among individuals carrying a particular genotype
- the influence of an expressed gene at the level particular individual phenotypes, analagous to the severity of a condition
What is penetrance? How is it expressed? Less than 100% penetrance is called what?
- presence of a gene that is not phenotypically expressed in all members of a family/population
- proportion of individuals of a specified genotype that express a trait that is normally associated with that genotype under a given set of environmental conditions
- incomplete penetrance
What are some reasons for incomplete penetrance? Incomplete penetrance is a phenomena associated only with what?
- age
- environment (nutrition)
- can also be the result of alleles at other loci that influence the expression of the trait
- dominant inheritance
What are complex (polygenic) traits also referred to as? Are there discreet classes of phenotypes? How are they measured? The majority of traits of interest are what? QTL can also be influenced by what?
- multi-factorial or quantitative traits (QTL)
- no
- along a spectrum
- continuously varying
- environmental factors (nutrition, infections, time of day)
What are some examples of complex (polygenic) traits?
- growth rate
- milk yield
- inflammatory response
- immune response
- hip or elbow parameters
What is epistasis?
Effects of one gene are modified by one or several other genes
What mutation causes lethal white foal syndrome? What coat pattern is this associated with? All white paints are what?
- homozygous EDNRB mutation
- Frame Overo
- 80% are heterozygous for EDNRB (so other genes are cuasing the whiteness cause if it was this one the foal would die)
