American Board of Genetic Counseling (ABGC) Practice Test 2026 – Your All-in-One Guide to Exam Success!

Huntington Disease typically has an age of onset ranging from 35 to 44 years. This late-onset characteristic is associated with the accumulation of CAG repeats in the HTT gene, which leads to the progressive neurodegeneration seen in this condition. As individuals age, the likelihood of having multiple CAG repeats increases, which correlates with the timing of symptom manifestation. Although symptoms can occasionally appear earlier or later, the majority of cases are diagnosed within this specific age range.

It is important to note that while some individuals may experience juvenile forms of Huntington Disease, which occur before the age of 20, these cases are much rarer and represent a smaller subset of the overall population affected by the disorder. Thus, the most prevalent age range for onset aligns with the provided choice.