Lecture 4- Genetics, Epigenetics, and Early Life Development Flashcards
Define Genome
1) The complete set of genetic material in organisms
2) all DNA sequences of an organism
Describe the features of DNA
1) Double helix
2) bade of base pairs A-T, G-C
3) nucleotides are the basic units of the DNA
Define gene
specific sequence of nucleotides that codes for a protein
Why are proteins important?
essential for all biological functions like building cells or regulating chemical reactions
What is dominant inheritance?
trait that observable in every generation
What is recessive inheritance?
trait that disappear in one generation, only to reappear in a subsequent one
How many chromosomes do humans have?
46
- autosomes- 22 pairs are same in both male and female
- sex chromosome differs
Define genotype
part of the genetic makeup of an individual which determines their characteristics e.g. eye colour
Define phenotype?
Set of observable characteristics of an individual resulting from the interaction of the genotype with the environment
What is monozygotic twin?
share 100% of DNA
What is a dizygotic twin?
share 50% of the gene
Why do we study twins?
As they share the same environment, comparing their similarities helps separate genetic and environmental factors
Define heritability
the proportion of phenotypic variation that can be explained by genetic variation
What did Polderman et al (2015) find?
1) meta-analysis find a 49% heritability between twins
What is Epigenetics?
- changes that do not alter the DNA sequence but affect how genes are expressed (environmental factors)
- influence of experience on gene expression
