Novel polymorphism of IFI44L associated with the susceptibility and clinical characteristics of systemic lupus erythematosus in a Chinese population

BACKGROUND

Interferon-inducible 44 like (IFI44L) is a newly discovered gene which has been reported to associate with the susceptibility of some infectious diseases, but there is no data on IFI44L SNP polymorphism associated with Systemic lupus erythematosus (SLE). In this study, we aimed to evaluate the association of IFI44L rs273259 polymorphism with the susceptibility and clinical characteristics of SLE in a Chinese population.

METHODS

576 SLE patients and 600 controls were recruited in this case-control study. Blood DNA was extracted and IFI44L rs273259 polymorphism was detected by TaqMan SNP Genotyping Assay Kit. The expression levels of IFI44L in Peripheral blood mononuclear cells were detected by RT-qPCR. The DNA methylation levels of IFI44L promoter were detected by bisulfite pyrosequencing.

RESULTS

The genotype and allele frequencies of IFI44L rs273259 in SLE patients have a significantly difference compared to healthy controls (P < 0.001). The genotype AG (vs. AA: OR = 2.849; P < 0.001) and the allele G (vs. A: OR = 1.454; P < 0.001) were associated with increased susceptibility of SLE. IFI44L rs273259 polymorphism was associated with clinical characteristics of SLE including malar rash (P < 0.001), discoid rash (P < 0.001), lupus nephritis (P < 0.001) and anti-Smith antibodies (P < 0.001). The expression levels of IFI44L were most significantly increased in genotype AG than genotype AA and GG (P < 0.01). The DNA methylation levels of IFI44L promoter were most significantly decreased in genotype AG than genotype AA and GG (P < 0.01).

CONCLUSIONS

Our results indicate novel polymorphism of IFI44L rs273259 was associated with the susceptibility and clinical characteristics of SLE in the Chinese population.

Transcriptome innovations in primates revealed by single-molecule long-read sequencing

Transcriptomic diversity greatly contributes to the fundamentals of disease, lineage-specific biology, and environmental adaptation. However, much of the actual isoform repertoire contributing to shaping primate evolution remains unknown. Here, we combined deep long- and short-read sequencing complemented with mass spectrometry proteomics in a panel of lymphoblastoid cell lines (LCLs) from human, three other great apes, and rhesus macaque, producing the largest full-length isoform catalog in primates to date. Around half of the captured isoforms are not annotated in their reference genomes, significantly expanding the gene models in primates. Furthermore, our comparative analyses unveil hundreds of transcriptomic innovations and isoform usage changes related to immune function and immunological disorders. The confluence of these evolutionary innovations with signals of positive selection and their limited impact in the proteome points to changes in alternative splicing in genes involved in immune response as an important target of recent regulatory divergence in primates.

Assessing the impact of acute respiratory illnesses on the risk of subsequent respiratory illness

BACKGROUND

Whether acute respiratory illnesses (ARIs), often associated with virus detection, are associated with lower risk for subsequent ARI remains unclear. We assessed the association between symptomatic ARI and subsequent ARI in young children.

METHODS

In a prospective cohort of Peruvian children <3 years, we examined the impact of index ARI on subsequent ARI risk. Index ARI were matched with ≤3 asymptomatic observations and followed over 28 days. We compared risk of subsequent ARI between groups using conditional logistic regression adjusting for several covariates, accounting for repeat observations from individual children.

RESULTS

Among 983 index ARI, 339 (34%) had an ARI event during follow-up, compared with 876/2826 (31%) matched asymptomatic observations. We found no significant association of index ARI and subsequent ARI risk during follow-up overall (aOR 1.10, 95% CI 0.98, 1.23) or when limited to index ARI with respiratory viruses detected (aOR 1.03, 95% CI 0.86, 1.24). Similarly, when the outcome was limited to ARI in which viruses were detected, no significant association was seen (aOR 1.05, 95% CI 0.87, 1.27).

DISCUSSION

ARIs were not associated with short-term protection against subsequent ARI in these children. Additional longitudinal studies are needed to understand drivers of recurrent ARI in young children.