. Author manuscript; available in PMC: 2018 Feb 1.

Published in final edited form as: Mol Psychiatry. 2017 Aug 1;22(11):1554–1561. doi: 10.1038/mp.2017.151

Table 1.

Genetic associations between copy number variants incorporating Complement 4A and Complement 4B genes and selected disorders/diseases.

Disease / disorder	Genetic Associations	Genotype assays	References
Schizophrenia (SZ)	Increased C4A copy number associated with risk for SZ	Droplet digital PCR	Sekar et al⁴⁰
Behcet’s disease (BD)	Increased C4A expression and IL-6 levels with 2 or >2 C4A copy number.	qPCR	Hou S et al¹²²
Systemic lupus erythematosus (SLE)	Deficiency - high risk for SLE; 0 or 1 copy of C4A - elevated risk for SLE; 3 or more copies of C4A - protective against SLE	PFGE of PmeI-Digested DNA qPCR qPCR	Yang et al¹²³ Wu et al¹²⁴ Yih et al¹²⁵
Grave’s disease (GD)	<2 copies of C4A associated with risk for vitiligo in patients with GD	qPCR	Liu et al¹²⁶
Crohn's disease (CD)	CD patients have overall lower C4L and higher C4S copies compared to controls	qPCR	Cleynen et al¹²⁷
Type1 Diabetes Mellitus	>2 copies of HERV-C4 in patients	qPCR	Mason et al⁶⁶
Alzheimer’s disorder	Overall increased copies of C4A or C4B in patients	qPCR	Zorzetto et al¹²⁸

PCR – polymerase chain reaction; PFGE - Pulsed-field gel electrophoresis; qPCR – quantitative PCR.