We defined this deletion further by identifying additional SIGLEC14 copy number variants and by determining the effect of SIGLEC14 copy number on the expression of SIGLEC14 and the neighboring SIGLEC5. We conclude that variants in ITIM/ITAM family members, including SIGLEC14, represent underappreciated potential genetic risk factors for AD. The gene discussed is SIGLEC5; the disease is Alzheimer disease.