Evaluation Of Allele Frequences Of Inherited Disease Genes In Subgroups Of Aqh

Front 1

Objective of paper?

Back 1

To estimate allele frequencies in elite performance subgroups of AQH's

Front 2

Allele frequencies of what?

Back 2

HYPP, LWFS, GBED, HERDA, PSSM

Front 3

Which subgroups of American Quarter Horses?

Back 3

Barrel racing, Cutting, Halter, Racing, Reigning, Western Pleasure, Working cow horse

Front 4

Where is point mutation in muscle of horses affected with HYPP?

Back 4

In sodium channel gene

Front 5

Which horses are affected more: homozygous or heterozygous?

Back 5

Homozygous

Front 6

What can trigger clinical signs of muscle dysfunction in HYPP horses?

Back 6

Stress &/or increased potassium in serum (under ideal management, defective gene does not have adverse effects)

Front 7

Is HYPP autosomal dominant or recessive?

Back 7

Autosomal Dominant

Front 8

What is LWFS?

Back 8

Lethal White Foal Syndrome

Front 9

Clinical signs of LWFS?

Back 9

-White/mostly white
-Colic signs w/in 12 hrs. of birth b/c of non-functioning colon

Front 10

Treatment for LWFS?

Back 10

None
Euthanasia b/c its fatal

Front 11

Is LWFS automosomal recessive or dominant?

Back 11

Autosomal Dominant

Front 12

What is GBED?

Back 12

Glycogen branching enzyme deficiency

Front 13

Signs of GBED:

Back 13

-Muscle weakness
-Abnormal glycogen formation in muscle

Front 14

What breeds are affected by GBED?

Back 14

Quarter horses & related breeds

Front 15

Is GBED autosomal recessive or dominant?

Back 15

Autosomal Recessive

Front 16

What is HERDA?

Back 16

Hereditary Equine Regional Dermal Asthenia
(genetic skin disease)

Front 17

Which breed of horses is HERDA predominantly found in?

Back 17

American Quarter Horse (particularly in cutting horses)

Front 18

Signs of HERDA?

Back 18

Hyperextensible skin, scarring, and severe lesions along the back of affected horses

Front 19

Is HERDA autosomal recessive or dominant?

Back 19

Autosomal recessive

Front 20

What is PSSM?

Back 20

Polysaccharide Storage Myopathy

Front 21

Which horses are affected by PSSM?

Back 21

QH bloodlines such as QH, American Paint horses, and Appaloosas

Front 22

What causes PSSM in horses?

Back 22

Abnormal accumulation of glycogen & abnormal polysaccharide in muscle tissue

Front 23

How can these diseases be diagnosed?

Back 23

Genetic testing

Front 24

How does genetic testing diagnose HYPP?

Back 24

Mutation in sodium channel gene is identified

Front 25

How is LWFS diagnosed by genetic testing?

Back 25

Mutation in endothelin B receptor is identified

Front 26

How is GBED diagnosed by genetic testing?

Back 26

Identify defect in GBE1 gene

Front 27

How is HERDA diagnosed by genetic testing?

Back 27

Mutation in peptidyl-prolyl isomerase B identification

Front 28

How is PSSM diagnosed by genetic testing?

Back 28

Mutation in glycogen synthase 1 is identified

Front 29

Which are the autosomal recessive diseases?

Back 29

LWFS, GBED, and HERDA

Front 30

What is an allele frequency?

Back 30

Used for both dominant & recessive diseases & is an estimate of the % of disease-causing alleles (variants) of a gene among all alleles in population

Front 31

What is carrier frequency?

Back 31

Used specifically for recessive diseases

Front 32

What disease allele was most restricted in its distribution within the breed?

Back 32

HYPP in AQH's

Front 33

What subpopulation of horses was HERDA prominent in?

Back 33

Cutting horses

Front 34

What group of horses was PSSM disease allele frequency greatest in?

Back 34

Halter subgroup

Front 35

How did the allele frequency for PSSM in the other subgroups compare to the controls?

Back 35

All other subgroups carried the PSSM allele at values less than those detected in the control population

Front 36

Were there any horses that had more than one disease allele?

Back 36

Halter subgroup

Front 37

Which diseases does the halter subgroup exhibit greater frequencies in?

Back 37

HYPP & PSSM

Front 38

Why does the halter subgroup exhibit greater frequencies of HYPP & PSSM?

Back 38

B/c of strong selection pressures used throughout the AQH industry

Front 39

How DNA testing be used to detect & exclude HYPP alleles?

Back 39

Rules of not breeding horses with HYPP alleles

Front 40

The term allele refers to:

Back 40

Variant of gene

Front 41

How many QH's exist?

Back 41

3,000,000

Front 42

Highest HYPP & PSSM in which subgroup?

Back 42

Halter

Front 43

Disease most broadly spread throughout the breeds:
GBED, HERDA, PSSM, all of the above

Back 43

All of the above

Front 44

AQH & APH harbor how many genetic diseases?

Back 44

5

Front 45

Mandatory testing for genetic disease is standard among registries....true or false?

Back 45

False

Front 46

Horses are diploid.....what is diploid?

Back 46

They have 2 sets of chromosomes (1 from mother & 1 from father)

Front 47

What is stratified sampling?

Back 47

Act of dividing large pop. into subgroups, using systematic sampling, then taking random samples from each subgroup