Horse Androgen Insensitivity Syndrome In Thoroughbred Variant 2 (AIS-T2)

The Androgen Insensitivity Syndrome (AIS) Thoroughbred Variant 2 DNA test is a vital tool for horse breeders and veterinarians. This genetic test identifies carriers of AIS, a condition affecting male horses' development despite normal XY chromosomes. Early detection through the AIS Thoroughbred Variant 2 test helps prevent breeding affected stallions, ensuring healthier offspring and maintaining breed integrity. Utilizing this DNA test supports informed breeding decisions and promotes the overall well-being of Thoroughbred horses. Stay ahead in equine genetics by incorporating the AIS Thoroughbred Variant 2 test into your breeding program today. Accurate and reliable, this test is essential for responsible Thoroughbred management.

Abbreviation : AIS-T2

Analysed mutation : AR c.2132C/T

Inheritance : X-Linked Recessive

Acronym

AIS-T2

Observed frequency

Normal

Clinical severity

Moderate

Clinical classification

Endocrine Diseases

Analysed mutation

AR c.2132C/T
p.(A711V)

Mode of inheritance

X-Linked Recessive (Complete)

Test summary:

The DNA test for Androgen Insensitivity Syndrome in Thoroughbred Variant 2 (AIS) helps identify horses carrying a genetic mutation that affects sexual development. AIS causes affected horses, typically genetically male, to develop female characteristics despite having XY chromosomes. This condition can impact fertility and breeding decisions in Thoroughbred populations. Early detection through DNA testing allows breeders to make informed choices and manage affected horses appropriately. Overall, the AIS test is a valuable tool for maintaining the health and integrity of Thoroughbred bloodlines.

Available from the pack : Basic

This DNA test is included starting from our pack Basic — and is also part of the packs Basic, Standard, Advanced, Complete.

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Introduction to Androgen Insensitivity Syndrome in Thoroughbred Variant 2

Androgen Insensitivity Syndrome (AIS) is a genetic condition that affects the development of sexual characteristics in individuals with XY chromosomes. In horses, particularly in the Thoroughbred breed, a specific variant known as Thoroughbred Variant 2 has been identified. This condition can have significant implications for horse breeding and performance.

Genetic Basis of AIS

AIS is caused by mutations in the androgen receptor gene, which results in a lack of response to androgens, the hormones responsible for male sexual development. In Thoroughbred Variant 2, the genetic mutation manifests in a manner that affects the horse's reproductive system and secondary sexual characteristics. Horses with this syndrome may appear externally female but possess XY chromosomes and internal male reproductive structures.

Clinical Manifestations

Horses affected by Thoroughbred Variant 2 typically display a range of clinical signs. These may include an absence of typical male reproductive organs, the presence of underdeveloped or abnormal genitalia, and a lack of behavioral traits typically associated with stallions. As a result, these horses may not be suitable for breeding purposes, leading to ethical and practical considerations in equine management.

Impact on Breeding and Performance

The presence of AIS in Thoroughbreds can significantly impact breeding programs. Understanding the genetic status of potential breeding stock is crucial for maintaining the integrity and quality of the breed. Horses identified as carriers of the AIS variant may be excluded from breeding to prevent the propagation of the condition, thus ensuring that the lineage remains strong and healthy.

Conclusion

Androgen Insensitivity Syndrome in Thoroughbred Variant 2 is a complex genetic condition that poses unique challenges for horse owners and breeders. By understanding the genetic underpinnings and clinical manifestations of this syndrome, stakeholders can make informed decisions that promote the health and viability of Thoroughbred horses. Ongoing research and genetic testing are essential for advancing knowledge and management practices related to AIS.

Breed recognized for the test : Androgen Insensitivity Syndrome In Thoroughbred Variant 2 (AIS-T2)

Thoroughbred

Interpretation of genotypes Genotype Status Learn more about the interpretation of genotypes FAQ: understanding the interpretation of result What does “Clear” mean? The animal does not carry the mutation. It will not develop the disease and will not pass it on. Is a “Carrier” serious? No. The animal is generally healthy but can transmit the mutation to its offspring. What if an animal is “Affected”? It carries two mutated copies. Clinical signs are expected depending on the disease. It should not be bred. Why are there differences between male / female? Some diseases are sex-linked, so their expression varies depending on the animal’s sex. The animal has two normal copies of the gene. No risk of developing or transmitting the disease. Heterozygous carrier: one mutated copy. The animal is usually not clinically affected but can pass the mutation to offspring. Male carrier or affected depending on the inheritance mode. Males have only one X or Y chromosome. Heterozygous female carrier: one mutated copy. She can pass the mutation on and may sometimes show mild clinical signs depending on the condition. Two mutated copies of the gene. The animal is at risk of developing the associated condition.

🧬 Interpretation of genotypes AIS-T2

Genotype

Status

🟡 N/N

Non-carrier - No Risk

❌ ♂ N/AIS-T2

Affected - At Risk

🟡 ♀ N/AIS-T2

Carrier - No Risk

❌ AIS-T2/AIS-T2

Affected - At Risk

FAQ: understanding the interpretation

What does “Clear” mean?

The animal does not carry the mutation. It will not develop the disease and will not pass it on.

Is a “Carrier” serious?

No. The animal is generally healthy but can transmit the mutation to its offspring.

What if an animal is “Affected”?

It carries two mutated copies. Clinical signs are expected depending on the disease. It should not be bred.

Why are there differences between male / female?

Some diseases are sex-linked, so their expression varies depending on the animal’s sex.

Genotype Forecast for Offspring Mother Father Non-carrier Carrier Affected Favorable cross: majority Carrier risk is predominant. Majority affected Filter by mother's genotype Filter by father's genotype All Predict Offspring The animal has two normal copies of the gene. No risk of developing or transmitting the disease. Heterozygous carrier: one mutated copy. The animal is usually not clinically affected but can pass the mutation to offspring. Male carrier or affected depending on the inheritance mode. Males have only one X or Y chromosome. Heterozygous female carrier: one mutated copy. She can pass the mutation on and may sometimes show mild clinical signs depending on the condition. Two mutated copies of the gene. The animal is at risk of developing the associated condition.

Predict Offspring

Filter by mother's genotype Filter by father's genotype

N/N (Non-carrier)

N/AIS-T2 (Carrier)

AIS-T2/AIS-T2 (Affected)

DNA Test FAQ

What does this DNA test detect?

This DNA test detects the mutation associated with Androgen Insensitivity Syndrome In Thoroughbred Variant 2 (AIS-T2) in order to identify clear, carrier, or at-risk animals.

Why test a breeding animal?

DNA testing helps breeders plan safer matings and reduce the risk of transmitting the mutation to offspring.

What is the inheritance mode of this test?

The inheritance mode reported for this test is X-Linked Recessive.

Which mutation is analysed in this test?

This test analyses the mutation AR c.2132C/T.

Is a carrier animal necessarily affected?

Not necessarily. Interpretation depends on the inheritance pattern and the resulting genotype.

References

Villagomez Daniel A F, Welsford Eastman G, King W Allan, Revay Tamas. Androgen Receptor Gene Variants in New Cases of Equine Androgen Insensitivity Syndrome. Genes (Basel). 2020 Jan 10;11(1):78. doi: 10.3390/genes11010078.

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