Name: Aqneursa (levacetylleucine) in Ataxia-telangiectasia: Prevalence of Ataxia-telangiectasia
Published: 2026-10-02T18:22:10-04:00

Estimated prevalence

“The estimated prevalence is 1-9:100,000” (opens the source at this quote in a new tab)

“Ataxia-telangiectasia occurs in 1 in 40,000 to 100,000 people worldwide.” (opens the source at this quote in a new tab)

Estimates stated by the manufacturer

“A-T is a rare, progressive, and prematurely fatal autosomal-recessive neurodegenerative disorder that affects an estimated 1 in 40,000 people.” (opens the source at this quote in a new tab)

“A-T is estimated to affect 1 in 40,000-100,000 people.” (opens the source at this quote in a new tab)

“Regulatory submissions planned in the US, Europe, and other jurisdictions for levacetylleucine in Ataxia-Telangiectasia, a neurodegenerative disease without any approved treatment and impacting approximately 1 in 70,000 people” (opens the source at this quote in a new tab)

Children known to the United States patient organization

“In the United States approximately 350 children with A-T are known to the patient organization A-T Children's Project” (opens the source at this quote in a new tab)

Participants in the Global A-T Family Data Platform

“Between 2016 and 2024, 624 participants with ataxia telangiectasia completed the questionnaire.” (opens the source at this quote in a new tab)
“Participant ages ranged from 0 to 64 years.” (opens the source at this quote in a new tab)

Europe: prevalence estimates and registry counts

“The Orphanet registry estimates the average prevalence of A-T at 1/100 000 children” (opens the source at this quote in a new tab)
“The prevalence of patients with A-T in Europe is estimated to be 1/150 000” (opens the source at this quote in a new tab)
“In Europe, 410 living A-T patients are currently listed on the European Society for Immunodeficiencies registry” (opens the source at this quote in a new tab)
“The most reliable estimates for the number of people with A-T, in the UK at least, are 3 per million” (opens the source at this quote in a new tab)

“Data of 659 A-T patients on age, gender, immunoglobulin levels IgA, IgG2, IgM, and lymphocyte counts, date of birth, and date of death (until 2014) were collected from the ESID registry and analyzed for mortality.” (opens the source at this quote in a new tab)

United Kingdom and Ireland: number of affected families and individuals

“Our estimate is that in the UK and Ireland there are currently approximately 150 families with approximately 170 cases of A-T, giving a prevalence of approximately 1 in 400,000.” (opens the source at this quote in a new tab)

Carrier frequency

“Given that complementation analysis has demonstrated the genetic heterogeneity of A-T, the A-T heterozygote frequency will probably fall between 0.68% and 7.7%, with 2.8% being the most likely estimate.” (opens the source at this quote in a new tab)

“About 1 percent of the United States population carries one altered copy and one normal copy of the ATM gene in each cell.” (opens the source at this quote in a new tab)

“Based on the incidence of A-T in the United States, the heterozygote frequency is estimated to be one in 200 persons” (opens the source at this quote in a new tab)

“The carrier frequency would therefore be of the order of 0.3% or approximately 1 in 300.” (opens the source at this quote in a new tab)

Founder populations with higher carrier frequency

Population	Heterozygote frequency
Druze population in northern Israel	“One in three to one in 15”
Moroccan and Tunisian Jewish population	“One in 81”
Romani population in Spain	“One in 36”

Rank among autosomal recessive hereditary cerebellar ataxias

“Friedreich ataxia was the most frequent AR-HCA, followed by ataxia with oculomotor apraxia or ataxia-telangiectasia.” (opens the source at this quote in a new tab)

Absence of population-based prevalence studies

“Despite our comprehensive literature search and review, we did not find population-based studies and were unable to determine the prevalence of A-T.” (opens the source at this quote in a new tab)
“Despite excluding duplicate cases, we found reports of 18247 cases. Most were classical A-T but 2.5% were reported as variants. The worldwide prevalence of variant A-T is not determined as yet.” (opens the source at this quote in a new tab)
“Although cases were reported from 74 countries, nearly a quarter of the cases were from the USA and another quarter from just four other countries (the UK, Italy, Germany, and Turkey).” (opens the source at this quote in a new tab)