Charcot-Marie-Tooth disease (CMT) refers to various types of inherited neuropathy that affect about 1 in every 2,500 people in the United States. For more information about the different types of CMT, see this NIH fact sheet.
SNPs in the SH3TC2 gene are involved in some cases of CMT and may also be associated with susceptibility to carpal tunnel syndrome.  Some cases of CMT are caused by copy number variants (CNVs) rather than SNPs. 
The New York Times web site has [interviews] with several people who are affected by CMT.
SNPs related to Charcot-Marie-Tooth disease include: