RationaleGenotypes associated to cow's milk allergy are unknown. They have not been replicated in independent population, and could be responsible for the marked variability in individual clinical response to cow milk proteins.The objective was to characterize haplogroups of the D-Loop region of mitochondrial DNA in a group of children allergic to cow's milk in order to arrive to a better knowledge of biological and genetic heritability in the etiology of the diseaseMethods.We studied 41 children of both sex aged 0 – 2 years, 11 allergic to cow's milk demonstrated by challenge and 30 healthy subjects (controls), from the urban area of Rio Cuarto City, Córdoba, Argentina. We performed Analysis of variants of D-loop region of the mitochondrial genome. The D-Loop region HVI, II and II of the mitochondrial genome was amplified by PCR, for which we used specific primers. Phylogenetic analysis was calculated using the program CLUSTAL OMEGA, the Neighbor–Joining, BLOSUM62 with data studied and recorded by Jukes-Cantor and then with Kimura-2ResultsThe cow milk allergic patients were divided in: (a) Atopic Dermatitis (AD) + Gastrointestinal Disease (GID) (n: 6) and (b) Rhinitis and Asthma (n: 5). We found the non described variant in transition of haplogroups, T16519C associated with (a) in 6/6 cases when compared with (b) negative in 5/5 cases and the control group (6/30), p= 0, 0312, RR: 2,900ConclusionsThese features suggest that this variant probably increases the possibility of suffering cow milk allergy associated with AD +GID. RationaleGenotypes associated to cow's milk allergy are unknown. They have not been replicated in independent population, and could be responsible for the marked variability in individual clinical response to cow milk proteins.The objective was to characterize haplogroups of the D-Loop region of mitochondrial DNA in a group of children allergic to cow's milk in order to arrive to a better knowledge of biological and genetic heritability in the etiology of the disease Genotypes associated to cow's milk allergy are unknown. They have not been replicated in independent population, and could be responsible for the marked variability in individual clinical response to cow milk proteins.The objective was to characterize haplogroups of the D-Loop region of mitochondrial DNA in a group of children allergic to cow's milk in order to arrive to a better knowledge of biological and genetic heritability in the etiology of the disease Methods.We studied 41 children of both sex aged 0 – 2 years, 11 allergic to cow's milk demonstrated by challenge and 30 healthy subjects (controls), from the urban area of Rio Cuarto City, Córdoba, Argentina. We performed Analysis of variants of D-loop region of the mitochondrial genome. The D-Loop region HVI, II and II of the mitochondrial genome was amplified by PCR, for which we used specific primers. Phylogenetic analysis was calculated using the program CLUSTAL OMEGA, the Neighbor–Joining, BLOSUM62 with data studied and recorded by Jukes-Cantor and then with Kimura-2 .We studied 41 children of both sex aged 0 – 2 years, 11 allergic to cow's milk demonstrated by challenge and 30 healthy subjects (controls), from the urban area of Rio Cuarto City, Córdoba, Argentina. We performed Analysis of variants of D-loop region of the mitochondrial genome. The D-Loop region HVI, II and II of the mitochondrial genome was amplified by PCR, for which we used specific primers. Phylogenetic analysis was calculated using the program CLUSTAL OMEGA, the Neighbor–Joining, BLOSUM62 with data studied and recorded by Jukes-Cantor and then with Kimura-2 ResultsThe cow milk allergic patients were divided in: (a) Atopic Dermatitis (AD) + Gastrointestinal Disease (GID) (n: 6) and (b) Rhinitis and Asthma (n: 5). We found the non described variant in transition of haplogroups, T16519C associated with (a) in 6/6 cases when compared with (b) negative in 5/5 cases and the control group (6/30), p= 0, 0312, RR: 2,900 The cow milk allergic patients were divided in: (a) Atopic Dermatitis (AD) + Gastrointestinal Disease (GID) (n: 6) and (b) Rhinitis and Asthma (n: 5). We found the non described variant in transition of haplogroups, T16519C associated with (a) in 6/6 cases when compared with (b) negative in 5/5 cases and the control group (6/30), p= 0, 0312, RR: 2,900 ConclusionsThese features suggest that this variant probably increases the possibility of suffering cow milk allergy associated with AD +GID. These features suggest that this variant probably increases the possibility of suffering cow milk allergy associated with AD +GID.