The AB variant is extremely rare; only a few cases have been reported worldwide.
How many people are affected by GM2-gangliosidosis, AB variant ?
<s>[INST] Answer the question truthfully, you are a medical professional. This is the question: How many people are affected by GM2-gangliosidosis, AB variant ? [/INST] \n The AB variant is extremely rare; only a few cases have been reported worldwide.</s>