“More than 30,000 Americans are living with HD.  Everyone has two Huntington (HTT) genes, one from each parent.  Huntington disease develops when one of those genes carries the mutation. In some families, appearance of symptoms happens early and earlier with each generation. The symptoms usually appear between the ages of 30-50.”

Honestly HD (https://www.honestlyhd.com/hd-overview?gclid=bc1d72d4cc7f10a028831af07b0f59e8&gclsrc=3p.ds&msclkid=bc1d72d4cc7f10a028831af07b0f59e8&utm_source=bing&utm_medium=cpc&utm_campaign=USA_MA_SEM_NB_PH_HonestlyHD-DTC-Research-Info-All-All-NANBA.All&utm_term=prevalence%20of%20huntingtons%20disease%20in%20the%20us&utm_content=Core)