![Genetic susceptibility Genetic susceptibility](https://cdn.magzter.com/1387285906/1729059179/articles/RJLihfycE1729083437419/GENETIC-SUSCEPTIBILITY.jpg)
IT is well-recognised that some breeds are more predisposed to certain conditions than others. Such conditions may have an inherited genetic basis, or be the result of selective breeding for highly desirable qualities, such as appearance or speed, at the cost perhaps of long-term soundness, for example.
A horse’s individual characteristics – such as size, colour or temperament – are dictated by his or her genetic constitution, or “genotype”.
In every cell of the horse’s body, there are about 22,000 protein-coding genes, consisting of specific segments of DNA. These are arranged on 32 pairs of chromosomes, one inherited from each parent.
“Alleles” are pairs of genes (again, one from each parent) which control the same trait, the final expression of which will depend on whether the allele is dominant or recessive.
Human blue eye-colour, for example, is a recessive trait and occurs only if both parents contribute a blue-eye allele. If one parent is brown-eyed however, the offspring is likely to have brown eyes, since the brown-eye allele is dominant.
TRIPLE TROUBLE
EQUINE genetic disorders encompass those health problems which occur when something goes wrong with the horse’s genotype – usually as a result of a mutation.
There are three types of genetic disorder. The most common are classic Mendelian or simple genetic disorders. There are two types:
Autosomal recessive, such as cystic fibrosis in humans – both inherited alleles need to be mutant to be clinically affected.
Autosomal dominant, for example Huntington’s disease in humans – only one of the inherited alleles needs to be mutant to be clinically affected.
هذه القصة مأخوذة من طبعة October 17, 2024 من Horse & Hound.
ابدأ النسخة التجريبية المجانية من Magzter GOLD لمدة 7 أيام للوصول إلى آلاف القصص المتميزة المنسقة وأكثر من 9,000 مجلة وصحيفة.
بالفعل مشترك ? تسجيل الدخول
هذه القصة مأخوذة من طبعة October 17, 2024 من Horse & Hound.
ابدأ النسخة التجريبية المجانية من Magzter GOLD لمدة 7 أيام للوصول إلى آلاف القصص المتميزة المنسقة وأكثر من 9,000 مجلة وصحيفة.
بالفعل مشترك? تسجيل الدخول
!['He's a terrier - a very classy terrier' 'He's a terrier - a very classy terrier'](https://reseuro.magzter.com/100x125/articles/5174/1925179/hUShtxWjT1733992303287/HES-A-TERRIER-A-VERY-CLASSY-TERRIER.jpg)
'He's a terrier - a very classy terrier'
Jonbon emulates some legendary chasers as a dual Tingle Creek victor, and trainer Dan Skelton scores a seasonal century
![Rupert Rupert](https://reseuro.magzter.com/100x125/articles/5174/1925179/fySUo_Umv1733992035304/RUPERT.jpg)
Rupert
This beautiful master's horse hates quad bikes and is \"scared of his rug\" but is dearly loved by both Nigel Peel and his son Jamie
![London's landmark moments London's landmark moments](https://reseuro.magzter.com/100x125/articles/5174/1925179/-sDw6mzFf1733991764912/LONDONS-LANDMARK-MOMENTS.jpg)
London's landmark moments
What makes London so special for dressage fans? Oscar Williams delves into its unique history, speaking to experts about their most treasured memories and the show's remarkable evolution in the sport
![Golden oldies take centre stage Golden oldies take centre stage](https://reseuro.magzter.com/100x125/articles/5174/1925179/NybBsm7a-1733991443625/GOLDEN-OLDIES-TAKE-CENTRE-STAGE.jpg)
Golden oldies take centre stage
The finals at London International are among the most regarded championships on the senior showing circuit. Alex Robinson investigates the finals and what's contributed to their popularity
![Winter wrapped up Winter wrapped up](https://reseuro.magzter.com/100x125/articles/5174/1925179/84H2jCD2v1733991170728/WINTER-WRAPPED-UP.jpg)
Winter wrapped up
With the long-range weather forecast suggesting a chilly winter ahead, how can equestrians prepare for the challenges of frost, ice and snow? Stephanie Bateman finds out
![Party time Party time](https://reseuro.magzter.com/100x125/articles/5174/1925179/Mt8eFsu-U1733990885946/PARTY-TIME.jpg)
Party time
From Whitaker vs Whitaker football matches to a hunting choir roaring carols, top riders know how to let their hair down at Christmastime. Netia Walker unearths the best festive parties
![Rocking their world Rocking their world](https://reseuro.magzter.com/100x125/articles/5174/1925179/tSSoNwVR-1733990177719/ROCKING-THEIR-WORLD.jpg)
Rocking their world
Rocking horses were once a common fixture in children's playrooms - or a charming trinket on a Christmas tree. Now, some are getting a new lease of life for grown-up enthusiasts, finds Liz Falkingham
![Winter watering Winter watering](https://reseuro.magzter.com/100x125/articles/5174/1925179/VKx91jT9_1733989635708/WINTER-WATERING.jpg)
Winter watering
Maintaining a horse's water intake is crucial, but can be tricky in the colder months. Karen Coumbe MRCVS explains why, and how to help
![Shetland Pony Grand National organiser Shetland Pony Grand National organiser](https://reseuro.magzter.com/100x125/articles/5174/1925179/bnDglNPmO1733989473056/SHETLAND-PONY-GRAND-NATIONAL-ORGANISER.jpg)
Shetland Pony Grand National organiser
Sebastian Garner on whittling down applicants, playing headmaster and the joy of watching Shetlands at full lick
![Peder Fredricson Peder Fredricson](https://reseuro.magzter.com/100x125/articles/5174/1925179/ECn70Sq3a1733988933781/PEDER-FREDRICSON.jpg)
Peder Fredricson
The Swedish flagbearer and four-time Olympic medallist tells Jennifer Donald about 2024's ups and downs, the key to social licence and silver linings