Lecture 13: Gene Expression Flashcards
How many pairs of chromosomes do we have
23 pairs of autosomes and 1 pair of sex chromosome
what mode of inheritance is Phenylketonuria disease
recessive
what mode of inheritance is Huntingtons disease
dominant
what mode of inheritence is sickle cell disease ?
incomplete dominance. The sickle cell is caused by a substitution causing a different amino acid in the primary structure- bad folding
How is an incomplete dominance genotype expressed
As neither allele is dominant over the other, the trait is expressed as a blend of effects from both alleles
What is an example of multiple allele inheritance
ABO blood groups
What is complex inheritance
This is when a phenotype is controlled by many possible genotypes. such as pigmentation
What is sex- linked inheritance
this refers to genes for traits that are present on X chromosome but not on Y chromosome
What is an example of sex linked inheritance and who does it affect the most
Red-green colour blindness where they don’t have red/green cones. It is a recessive condition but males not having an X chromosome have no chance to just be a carrier so most susceptible
If the child is a boy and has a sex linked inherited condition and his father is affected this came from
the mother, father contributes Y chromosome
What is the process of discovering the modes of inheritance
cells from patient-> extract DNA -> prepare for sequencing -> sequence-> align to known reference -> identify variations -> assess functional consequences
What is the genetics research cycle
Patients & family -> description of phenotype -> identification of underlying genes -> characterising mechanism-> diagnostic management and treatments.
