Abstract Meeting the challenges brought by the COVID-19 pandemic requires an interdisciplinary approach. In this context, integrating knowledge of immune function with an understanding of how genetic variation influences the nature of immunity is a key challenge. Immunogenetics can help explain the heterogeneity of susceptibility and protection to the viral infection and disease progression. Here, we review the knowledge developed so far, discussing fundamental genes for triggering the innate and adaptive immune responses associated with a viral infection, especially with the SARS-CoV-2 mechanisms. We emphasize the role of the HLA and KIR genes, discussing what has been uncovered about their role in COVID-19 and addressing methodological challenges of studying these genes. Finally, we comment on questions that arise when studying admixed populations, highlighting the case of Brazil. We argue that the interplay between immunology and an understanding of genetic associations can provide an important contribution to our knowledge of COVID-19.
Several phylogeographic studies of seabirds have documented low genetic diversity that has been attributed to bottleneck events or individual capacity for dispersal. Few studies have been done in seabirds on the Brazilian coast and all have shown low genetic differentiation on a wide geographic scale. The Kelp Gull is a common species with a wide distribution in the Southern Hemisphere. In this study, we used mitochondrial and nuclear markers to examine the genetic variability of Kelp Gull populations on the Brazilian coast and compared this variability with that of sub-Antarctic island populations of this species. Kelp Gulls showed extremely low genetic variability for mitochondrial markers (cytb and ATPase) and high diversity for a nuclear locus (intron 7 of the β-fibrinogen). The intraspecific evolutionary history of Kelp Gulls showed that the variability found in intron 7 of the β-fibrinogen gene was compatible with the variability expected under neutral evolution but suggested an increase in population size during the last 10,000 years. However, none of the markers revealed evidence of a bottleneck population. These findings indicate that the recent origin of Kelp Gulls is the main explanation for their nuclear diversity, although selective pressure on the mtDNA of this species cannot be discarded.
True neurogenic thoracic outlet syndrome (TOS) is an uncommon disorder despite of be a frequent reason for referral to the EMG laboratories. We describe the second case in the literature of true TOS in a competitive swimmer with progressive weakness and severe atrophy of the left thenar eminence. EMG showed lower trunk plexopathy. X-ray and MRI of the cervical spine and brachial plexus were normal. Surgical exploration evidenced the lower trunk retracted and pulled by a fibrous band. It was excised and neurolysis of the plexus was done with gradual improvement of function. We discuss the possible pathophysiology of this association.
A síndrome do desfiladeiro torácico verdadeiro é condição incomum, apesar de ser uma razão freqüente de encaminhamento aos laboratórios de eletroneuromiografia. Nós descrevemos o segundo caso na literatura desta doença rara em um nadador competitivo com fraqueza e atrofia severa da eminência tenar esquerda. A ENMG mostrou plexopatia do tronco inferior. O RX e as ressonâncias magnéticas da coluna cervical e do plexo braquial foram normais. Exploração cirúrgica mostrou o tronco inferior tracionado por uma banda fibrosa. Ela foi ressecada e procedeu-se a neurólise do plexo com melhora gradual da função. Nós discutimos a possível fisiopatologia desta associação.