Cat Genetics: Qualitative Traits

Question 1

Qualitative vs. Quantitative

Answer 1

Qualitative:
* Aka Mendelian, single-gene - a quality like a hair type, color, or spot pattern
* Controlled by a few genes (meaning inherited traits)
* Discrete variables

Quantitative:
* Many genes, continuous variables

Question 2

Main Cat Colors

Answer 2

Only 2 base pigments:
* red/yellow/orange (pheomelanin)
* Black (eumelanin)

Everything else is modification of those

Question 3

Color: Agouti

Answer 3

Banded hair color
A - agouti
a - non-agouti (solid colored cat - white is an exception)

Question 4

Black, brown

Answer 4

B - solid black
b - chocolate brown
b^l red brown (cinnamon)

Question 5

Color points

C, c^b, c^s, c^a, c

Answer 5

C - full color
c^b - Burmese: darker face, fades out
c^s - Siamese: dark points, lighter body
c^a - blue-eyed white: deafness fairly common in these cats
c - albino (pink eyes): rare

Question 6

Cause of Darker “Points” - in Siamese Cats

Answer 6

• Put Siamese cats in a very cold environment and put insulated vests on them
• Bodies where they had the vests on where white, where they were cold they produced more pigment
• Kittens are born all white bc warm inside the mother

Question 7

Dilution, Pigment Inhibition

Answer 7

Dilution: recessive
D- intense color
d - dilute color

Pigment Inhibition: dominant
I - pigment inhibition - silver or “smoke” coloring
i - normal pigmentation

Question 8

Calico

Answer 8

multiple colors
O - orange
o - non-orange
Calicos are sex-linked (carried in the X-chromosome)
Oo - heterozygous will be a calico - mostly always female

Question 9

Spots

Answer 9

Incompletely dominant
S - white spotting
s - no spotting
Probably several other background genes involved with this

Question 10

Tabby: T^A, T, t^b

Answer 10

T^A - Abyssinian tabby (sandy looking, sometimes stripes on head or tail)
T - striped (Mackerel) tabby (parallel stripes)
t^b - (blotched) tabby - bullseye stripes

Question 11

White

Answer 11

W - dominant white
w - presence of color
Crossing 2 white cats won’t necessarily produce white kittens (if there are heterozygous white cats they carry recessive allele)

Question 12

Hair Type

Answer 12

H - presence of hair
h - hairlessness
L - short hair
l - long hair
Wh - wire hair
wh - normal hair

Question 13

Folded ear

Answer 13

Fd - folded ears
fd - normal ears (ear stays folded over for life)

Question 14

American curl (ears curl back)

Answer 14

Dominant mutation - people start selecting

Question 15

Sphynx

Answer 15

cross of folded ear and curled ear

Question 16

Manx tail

Answer 16

M - absence of tail
m - normal tail
Mm have manx tails
* M is a homozygous lethal - when cat is homozygous (MM), it will kill the cat usually when it is a developing fetus
* This allele interferes with spine and backbone development (one copy removes the tail, 2 copies will probably interfere w spine)

Question 17

How can we produce tailless kittens without producing homozygotes?

Answer 17

Take one parent manx and other non-manx

Question 18

Japanese bobtail

Answer 18

very short tail

Question 19

Polydactyly

Answer 19

Pd - polydactyly (more than normal # of toes)
pd - normal # of toes

Question 20

Munchkin, Twisty

Answer 20

• Munchkin - form of dwarfism, legs are not as long as normal cat
• Twisty - front feet and sometimes back feet are not developed right, more plantigrade than digitigrade

Question 21

Mutations

Answer 21

• Happen spontaneously
• Happen fairly often, but most die out
• May be deletions, additions, etc.
• Not initiated by humans (usually)
• Often considered a negative thing
• Allow for evolution (a way for new alleles to be introduced to a population - genetic variation)

Question 22

Genetic Conditions General: purebreds, crossbreds

Answer 22

• Many health conditions that have genetic component are breed-specific

Purebreds and Crossbreds
* fewer cats (than dogs) are purebreds
* fewer genetic diseases known in cats
* more genetic diseases in purebreds?

Question 23

Purebreds and Genetic diseases

Answer 23

Inbreeding
* breeding of closely related individuals
* increases homozygosity
* pros: necessary to solidify breed characteristics
* cons: can increase incidence of phenotypes of deleterious recessive genes (homozygous for genes that you don’t want)

On the other hand, genetic basis (for disease) can be seen when pedigrees (recorded ancestries) are known - so maybe just more noticeable

Question 24

Hypoallergenic cat

Answer 24

• Allerca Lifestyle Pets company
• Most allergies are to a glycoprotein produced by cat (saliva, sebaceous glands) - NOT THE HAIR, might be on the hair
• Discovered mutation in some cats (genetics)
• Selectively bred these cats (with DNA confirmation)
  (Maybe)

Question 25

Genetics Savings and Clone

Answer 25

Company that will clone your cat
$50K price tag
Take DNA from donor cell, insert into egg, put into female

Question 26

Cloning Comments Keep in Mind

Answer 26

Very expensive
May take many tries
Not everything is genetic:
* Behavior may be quite different
* Other environmental influences

Question 27

Glow in the Dark Cats

Answer 27

Lab test
Took a luminescence gene and put into cats