SORL1 and familial Alzheimer disease: While sporadic AD (SAD), the most common form of AD, has a multifactorial component, including risk factors such as the presence of apolipoprotein E (ApoE) ε4, familial AD (FAD) due to genetic variations in APP, PS1, PS2, and sortilin-related receptor 1 (SORL1) genes [23,24].