In the eastern suburbs of Sydney there is a psychologist, Sue Hawkins, who has the Medicare registration and also has experience with HD and genetic issues. You can find her contact details on www.suehawkins.com Please contact us again if you have any further questions. Fiona i have a low cag count of 38. But i already have HD. I thought i would have late onset HD because i have a low cag count. what has happened ? Name: sally capel Question: i have a low cag count of 38. But i already have HD. I thought i would have late onset HD because i have a low cag count. what has happened ? For all people at risk of HD, the size of the CAG repeat is a major factor in determining the age at which symptoms appear. That is, the lower the CAG number the later the average age of onset. Conversely, the higher the CAG number the lower the average age of onset. The key word here is average. To put it another way, if 100 people have a CAG number say of 38 then most will have an age of onset in their older years, but some people will still get HD at a younger age including a few in their 30's and 40's.  For this reason, doctors and genetic counsellors can never tell you as an individual when the HD will appear. The main significance of having a positive result is that one day you might