HLA-DQA1, HLA-DQB1, and IGHG1 were found to be pivotal in the top biological pathways and diseases in long COVID, which overlapped with ME/CFS with the addition of IGHG3, CCL2, CEACAM3, and IFNA6. The gene discussed is IGHG3; the disease is myalgic encephalomeyelitis/chronic fatigue syndrome.