In this article, we present data on endothelial Nitric Oxide Synthase (eNOS) gene T786C and G894T polymorphisms in Greek steady-state Sickle Cell Disease patients in comparison to healthy controls. Moreover, eNOS mRNA levels were determined in peripheral blood samples from 18 patients and 9 controls. This article complements our recently published article named "Prognostic value of eNOS T786C and G894T polymorphisms in Sickle Cell Disease" (I. Armenis, V. Kalotychou, R. Tzanetea, Z. Kontogeorgiou, D. Anastasopoulou, M. Mantzourani, M. Samarkos, K. Pantos, K. Konstantopoulos, I. Rombos, 2016) [1].

Depressive disorders and obesity are highly comorbid conditions sharing genetic, metabolic, and immunological substrates. In a cross-sectional analysis of 53 participants across the obesity spectrum (lean n = 12; overweight n = 9; obese n = 32), a depression genetic risk score (d-GRS) correlated positively with BMI (ρ = 0.379, p = 0.005) and with serum CRP (ρ = 0.322, p = 0.031), consistent with the known genetic coarchitecture between depression and inflammatory traits. The d-GRS was tested against 116 flow-cytometry-derived immune parameters using Spearman rank correlation. The most consistent immune association at nominal significance (p < 0.05, uncorrected) involved the immunoregulatory CD56^brightCD16⁻ natural killer (NK) cell subset across two independent gate representations (ρ = 0.444, p = 0.004), remaining significant after sequential adjustment for BMI, sex, age, and physical activity (adjusted ρ range: 0.439–0.469), with no equivalent association for a genetically independent obesity GRS. In silico analysis of d-GRS SNP-tagged genes identified several with documented roles in NK cell trafficking, activation, and cytokine production, providing a putative mechanistic basis for this association. These findings nominate the CD56^brightCD16⁻ NK cell subset as a candidate immunological link between depression genetic susceptibility and neuroimmune mechanisms, warranting independent replication and functional characterisation in prospective cohorts.