Genetic Diseases 1 Flashcards
Pellagra
Skin abnormalities, intolerance to sun - caused by vitamin B3 deficiency
Inherited but not genetic
Brachydactyly
Short hands stubby fingers
Dominant Mendelian Inheritance
Achondroplasia
Dwarfism
Dominant Mendelian Inheritance
Huntington’s Disease
Neurodegenerative, causes production of defective huntington protein - motor abnormalities “chorea”
Dominant Mendelian Inheritance
-> Nancy Wexler
Chromosome duplication
>23 CAG repeats on huntington gene
Haspburg Lip
Spanish monarchy - eg Philip IV
Dominant Mendelian Inheritance
Cystic Fibrosis
Failure in transport protein that moves liquid across cell membranes –> lungs clogged w/ mucus
Recessive Mendelian Inheritance
1/25 in Europeans
Albinism
Absence of pigment in hair/skin
Recessive Mendelian Inheritance
Rice: high yield+short stalks
Recombination of high yield tall X low yield short
Recombination
Flu
H1N1 differ from 1918 massive flu virus by 1bp
-> Recombination
Tay-Sachs Disease
Deficiencies in hexosanimade enzyme activity - deterioration of nerve cells and of mental and physical abilities
Recessive Incomplete Dominance
Blood groups
A - B, codominance
The phenotypic effects of a gene’s allele fully & simult expr in htz
A,B,O - multiple alleles
Sickle Cell
Sickle cell trait: htz, have equal concentrations of normal and “sickle” haemoglobin
1 aa change-> anaemia, heart failure, paralysis, enlarged spleen, brain damage, poor circulation, malaria resistance
=> also pleiotropy
Eye Colour
Multiple alleles
Mouse coat color
yellow vs WT -> lethal recessive alleles
Manx Cat
Tail is a short stub - lethal recessive alleles
Blue-eyed deaf white cats
Deficiency in melenin - affects pigment but there is also melanin in ear that does sth
Pleiotropy
Aggressive tabby cats
Pleiotropy
Usher Syndrome
Deafness and blindness
-Pleiotropy
Sex Limitations
Testosterone
- add testosterone to a female -> exhibits various male secondary sex characters (eg beard, baldness)
Autism
Several genes affect 1 character - 1 locus alters phenotype produced by other locus
Mouse coat colour (similar in horses)
At least 5 interacting loci: A-color distribution, B-color, C-presence/abs (epistatic), S-pigment distribution
- Gene Interaction
Secretor Phenotype
Interaction bw Se locus and ABO blood group locus
Se / Sese - produce ABO substances in saliva, semen
- Dominant but gene interaction
