(e).

Author	Title	Year	Country	Objective	Sample size	BNDF genetic variant	Genotypic frequency (Val/Val)	Laboratorial method	Results	p-value (case vs. control)	Odds ratio
Tatham et al. [30]	The 5HTTLPR and BDNF polymorphisms moderate the association between uncinate fasciculus connectivity and antidepressants treatment response in major depression	2017	Canada	Assess if the white matter integrity indices and the association between 5HTTLPR and BDNF (val66met) polymorphisms predict the magnitude of change in depressive symptoms after antidepressant treatments.	n = 46 F = 26 (56.5%) M = 20 (43.5%)	rs6265	80.44% (n = 37)	PCR-RFLP	A (Met) allele carriers exhibited a reduction in MDD improvement; furthermore, BDNF gene polymorphisms significantly impacted the uncinate fascicle's FA values.	0.13	—
Tatham et al. [17]	White matter integrity in major depressive disorder: implications of childhood trauma, 5HTTLPR and BDNF polymorphisms	2016	Canada	Evaluate how childhood neglect and the 5HTTLPR and BDNF polymorphisms influence the brain's myelin integrity in MDD.	n = 55	rs6265	80% (n = 42)	PCR-RFLP	A (Met) patients have reduced FA values in the nonisolated fascicle compared with GG (Val/Val) patients (p = 0.005). BDNF polymorphism moderated the association between the depression severity and FA levels in the uncinate fascicle (p = 0.02).	0.197	—
Jaworska et al. [31]	The influence of 5HTTLPR and Val66Met polymorphism on cortical thickness and volume in limbic and paralimbic regions in depression: a preliminary study	2016	Canada	Evaluate the 5HTTLPR and BDNF gene polymorphism influence on cortical thickness or brain volume, in the paralimbic and limbic regions, in the MDD.	n = 43 F = 26 (60.5%) M = 17 (39.5%)	rs6265	81.3% (n = 35)	PCR and RFLP	BNDF polymorphism did not affect the paralimbic and limbic structures' cortical thickness or cerebral volume.	>0.05	—