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Page 226 Puyana et al. J Transl Genet Genom 2022;6:223-239 https://dx.doi.org/10.20517/jtgg.2021.51

Variables
Race/ethnicity was self-reported. Weight as of June 17, 2015, was also obtained from the patients’ electronic
medical record (n = 513) and compared to weight at the time of consent. BMI was calculated according to
the National Institute of Health (NIH) conversion formula using height and weight at the time of
enrollment. Classification of BMI was performed using the World Health Organization index as follows:
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BMI < 18.50 kg/m as underweight, BMI 18.50-24.99 kg/m as normal weight, BMI 25.0-29.99 kg/m as
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overweight, BMI 30.00-34.99 kg/m as obese class I, BMI 35.00-39.99 kg/m as obese class II, and BMI ≥
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40.00 kg/m as obese class III. Eligibility criteria for bariatric surgery were defined using NIH guidelines for
the management of overweight and obesity (BMI ≥ 40 kg/m , or BMI ≥ 35 kg/m with at least one obesity-
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related comorbidity).
Whole blood was processed within 2 h of phlebotomy and stored at -80 °C. DNA was isolated from whole
blood using the Biamp Blood Kit (QIAGEN Inc., Chatsworth, CA). The genomic DNA extracted from
whole blood was used for the genotyping performed by the University of Miami Hussmann Institute for
Human Genomics using the Illumina Omni 2.5-8 v1 BeadChip and Illumina’s Genome Studio Software.
Samples with raw call rates < 99%, duplicates, gender mismatches, or relatedness were excluded. SNPs with
low calling rates (< 95%) and low minor allele frequencies (MAF < 0.05) were also excluded. Additionally,
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markers with significant deviations from Hardy-Weinberg Equilibrium (P < 1 × 10 ) were removed.
CRP levels (mg/L) were measured using plasma samples taken before the start of the RT and at the end of
RT using the high sensitivity CRP ELISA kit (Cal biotech, Spring Valley, CA) according to the
manufacturer’s protocol. Briefly, frozen plasma samples were thawed and centrifuged at 10,000 rpm for
3 min. The clarified supernatant was diluted, and 10 μL were added to duplicate CRP-coated wells. 100 μL of
enzyme conjugate was then added, and the plate was agitated briefly to mix. Following 1 h of incubation at
room temperature, the unbound mixture was removed, and the wells were washed three times with wash
buffer. The absorbance at 450 nm was determined using the Synergy HT microplate reader (Biotech
Instruments, Winooski, VT). A standard curve with known concentrations of CRP (0.2 to 10 mg/L) was
generated and levels of CRP were extrapolated based on the standard curve.

Statistical analysis
After genotyping quality control, 97 samples were excluded. Patients who reported race/ethnicity other than
AA, HW, or NHW (n = 11) or who were classified as underweight (n = 2) were also excluded. The final
dataset contained 403 patients. Descriptive analyses (mean, standard deviation, median, range, and
frequency) were used to identify differences in the participant’s characteristics by the study as well as by
race/ethnicity. SAS version 9.3 for Windows (SAS Institute, Cary, NC, USA) was used to perform the
logistic regression analysis using the PRS to predict obesity status (obese = BMI ≥ 30.00 kg/m ; not obese =
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18.50-29.99 kg/m ).
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Linear regression models were fitted using obesity PRS as a predictor of BMI and CRP levels at baseline.
Analysis of variance (ANOVA) was performed on the mean PRS scores among three race/ethnic groups;
further Tukey test was performed to find significant differences between each specific group. The obesity
PRS was categorized into 4 levels based on quartiles (level 1: PRS ≤ Q1; level 2: Q1 < PRS ≤ Q2; level 3: Q2 <
PRS ≤ Q3; and level 4: PRS > Q3). PRS levels were compared by participant’s race/ethnicity (AA, HW,
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NHW), obesity status, and bariatric surgery eligibility using the χ test or fisher’s exact test. The significance
level was set at alpha = 0.05. Odds ratios (ORs), 95% confidence intervals (95%CI), and P values were
calculated.