Spanish cases and controls assessed by GWAS
Spanish patients were recruited in the Allergy Service, Carlos Haya
Hospital, Malaga, Spain. From the initial samples of the 436 patients
and 1218 control subjects, 413 and 1124 passed quality control for HLA
loci, respectively, and were retained in the final statistical analyses.
We used 184 additional control subjects from the same population, which
allowed us to perform the association study with 1308 controls. The
retained population included 98 cases with delayed hypersensitivity to
penicillins diagnosed as previously described18 and
315 cases with immediate allergic reactions from the aforementioned
study.11 They ranged from 16 to 60 years old. The
1,308 controls were from Malaga and Salamanca (Spain), as previously
described.11 Age- and gender-paired volunteers were
recruited in preventive-care consultations. All of them tolerated
amoxicillin and other penicillins on different occasions, and they had
no histories of allergic, dermatological, or respiratory diseases.
Subjects who had never taken penicillins and those with a C-reactive
protein blood concentration higher than 5 mg/L were excluded from the
control group. All patients and controls were of Caucasian origin.
Before allergy tests, all subjects received information about possible
related risks, and written informed consent for participating in the
study and providing DNA samples was obtained from each patient or the
parents of those under 18 years of age. The respective institutional
review boards approved the protocol.