2.2 Data source
Publicly available genome-wide association studies (GWAS)
summaries were used in this
study. Data for SNPs associated with
the allergic disease was from the
largest GWAS to date (meta-analysis of 13 studies), all of the European
ancestry, including 180,129 cases with self-reported asthma and/or hay
fever and/or eczema and 180,709 controls without any of these
symptoms10. (Figure 2)
Genetic association estimates for hay fever, AR, or eczema
diagnosed by the doctor (104,559
cases and 350,890 controls) and asthma diagnosed by the doctor (52,504
cases and 402,945 controls) were acquired from the UK Biobank (UKB), a
population-based cohort study involving over half a million volunteers
recruited in the United Kingdom
(https://www.ukbiobank.ac.uk/)11. (Figure 3)
Summary-level statistics for AR (5,527 cases and 212,387 controls), AD
(7,024 cases and 198,740 controls),
allergic asthma (4,859 cases and 135,449 controls),
non-allergic asthma (3,155 cases and
184,148 controls), mixed asthma (724 cases and 135,448 controls) and
childhood asthma (age<16 years) (3,025 cases and 135,449
controls) were retrieved from another large-scale biomedical European
databases of FinnGen
(https://www.finngen.fi/en),
launched in 2017, unique in its integration of genomic information with
digital medical data12. (Figure 3) The selection of
GWAS summaries for each phenotype in this study followed the following
principle: when no data for the
phenotype was available in the UKB or no available IVs (the F statistics
of SNPs were all <10) could be obtained from the UKB, GWAS
data will be obtained from the FinnGen.
The latest and largest GWAS data
sets for SARS‐CoV‐2 infection (159,840 cases and 2,782,977 controls) and
severe respiratory confirmed COVID-19 (18,152 cases and 1,145,546
controls) were acquired from the COVID‐19 Host Genetics Initiative (HGI)
GWAS meta‐analysis round 7 without the 23andMe cohort, released on 8
April 202213. Details of the cohorts included in this
meta-analysis and the quality control were available athttps://www.covid19hg.org/results/r7/ .
The population included was predominantly European.