Quantitative Analysis of SARS-CoV-2 Antibody Status between Patients with Cancer and Healthy Individuals with Extended Vaccination Dosing Intervals in Canada.

(1) Background: To date, data addressing the antibody response of cancer patients to SARS-CoV-2 vaccines are limited. To our knowledge, this is the first report to evaluate humoral immunity. responses in Canadian cancer patients. (2) Methods: 116 cancer patients and 35 healthy participants were enrolled in this cross-sectional study. The interval between the first and second doses were closely matched during analysis. IgG antibodies against the SARS-CoV-2 spike receptor-binding domain were determined using an enzyme-linked immunosorbent assay (ELISA). (3) Results: Following two doses of SARS-CoV-2 vaccine (including BNT162b2, AZD1222, and mRNA-1273), the mean serum anti-spike protein antibody level was 382.4 BAU/mL (binding antibody unit, SD ± 9.4) in the control group, 265.8 BAU/mL (±145.7) in solid cancer patients, and 168.2 BAU/mL (±172.9) in hematological cancer patients. Observed differences were significantly lower in both solid and hematological groups when comparing to the control group (p ≤ 0.0001). In solid cancer group, patients with cytotoxic chemotherapy demonstrated significantly lower antibody levels (p < 0.01), whereas the rest of the patients showed similar antibody levels as the healthy control. Antibody levels were lower in those on treatment than those off treatment in patients with hematological malignancies (p < 0.0001) but not for those with solid cancers (p = 0.4553). (4) Conclusions: After two doses of the SARS-CoV-2 vaccination, patients with solid and hematological malignancies demonstrated impaired serological responses. This was particularly prominent if there was cytotoxic chemotherapy or systemic therapy in solid and hematological cancer, respectively.

Admixture mapping in two Mexican samples identifies significant associations of locus ancestry with triglyceride levels in the BUD13/ZNF259/APOA5 region and fine mapping points to rs964184 as the main driver of the association signal.

We carried out an admixture mapping study of lipid traits in two samples from Mexico City. Native American locus ancestry was significantly associated with triglyceride levels in a broad region of chromosome 11 overlapping the BUD13, ZNF259 and APOA5 genes. In our fine-mapping analysis of this region using dense genome-wide data, rs964184 is the only marker included in the 99% credible set of SNPs, providing strong support for rs964184 as the causal variant within this region. The frequency of the allele associated with increased triglyceride concentrations (rs964184-G) is between 30-40% higher in Native American populations from Mexico than in European populations. The evidence currently available for this variant indicates that it may be exerting its effect through three potential mechanisms: 1) modification of enhancer activity, 2) regulation of the expression of several genes in cis and/or trans, or 3) modification of the methylation patterns of the promoter of the APOA5 gene.