Aiming to evaluate the
role of ten functional polymorphisms in
long COVID , involved in major inflammatory,
immune response and
thrombophilia pathways, a cross-sectional sample composed of 199
long COVID (LC)
patients and a cohort composed of 79 COVID-19
patients whose follow-up by over six months did not reveal any evidence of
long COVID (NLC) were investigated to detect
genetic susceptibility to
long COVID . Ten functional polymorphisms located in
thrombophilia -related and
immune response genes were genotyped by
real time PCR . In terms of clinical outcomes, LC
patients presented higher
prevalence of
heart disease as preexistent
comorbidity . In general, the proportions of symptoms in acute phase of the
disease were higher among LC
patients . The
genotype AA of the interferon gamma (IFNG)
gene was observed in higher frequency among LC
patients (60%; p = 0.033). Moreover, the
genotype CC of the
methylenetetrahydrofolate reductase (MTHFR)
gene was also more frequent among LC
patients (49%; p = 0.045). Additionally, the frequencies of LC symptoms were higher among carriers of IFNG
genotypes AA than among non-AA
genotypes (Z = 5.08; p < 0.0001). Two polymorphisms were associated with LC in both inflammatory and
thrombophilia pathways, thus reinforcing their
role in LC. The higher frequencies of acute phase symptoms among LC and higher frequency of underlying comorbidities might suggest that
acute disease severity and the triggering of
preexisting condition may
play a
role in LC development. / Secretary of
Science ,
Technology and Higher, Professional and Technological
Education of the
State of Pará (SECTET #09/2021),
Amazon Foundation for
Research Support (FAPESPA)#006/2020 and #060/2020, The Coordination for the Improvement of
Higher Education Personnel (CAPES), National Council for Scientific and
Technological Development (CNPQ)#401235/2020-3.