Angiotensin-Converting Enzyme Ins/Del Polymorphism and Body Composition: The Intermediary Role of Hydration Status.
BACKGROUND
The well-known insertion/deletion polymorphism (rs4646994) of the angiotensin-converting enzyme (ACE) gene has been previously associated with obesity, blood flow, muscular strength, and ACE enzyme activity. Despite the relevant role of ACE in homeostasis, few data are currently available on the relationship between rs4646994 and hydration status. Thus, we tested the association between the ACE Ins/Del polymorphism, body composition, and hydration status in a young Italian population.


METHODS
A total of 306 healthy children and adolescents who regularly practice sports were recruited. Anthropometric, bioimpedentiometric parameters, and urine samples were collected, while ACE rs4646994 genotyping was performed on DNA from buccal swabs. General linear models were used for association testing.


RESULTS
The ACE Ins/Del polymorphism was associated with body composition. Ins/Ins individuals had higher phase angle (PhA) and body cellular mass index (BCMI) values. A significant influence of the ACE rs4646994 according to hydration status on body composition was also identified. In particular, Ins/Ins individuals displayed higher PhA and BCMI values only if norm-hydrated, while they showed values similar to Del carriers if dehydrated.


CONCLUSIONS
Our results confirm the relationship between the ACE Ins/Del polymorphism and body composition and suggest a role for hydration status in modulating this relationship. These interesting preliminary results warrant further investigation to disentangle the genetic role of ACE on hydration homeostasis.
School of Advanced Studies, University of Camerino, Camerino, Italy.
Laura
L
Bordoni
Valerio
V
Napolioni
Francesca
F
Marchegiani
Emilio
E
Amadio
Rosita
R
Gabbianelli
D000293:Adolescent; D020087:Alu Elements; D001823:Body Composition / Q000235:genetics*; D015992:Body Mass Index; D002648:Child; D005260:Female; D056726:Genetic Association Studies; D006801:Humans; D054643:INDEL Mutation; D007558:Italy; D016014:Linear Models; D008297:Male; D008957:Models, Genetic; D054647:Nutrigenomics; D000074267:Organism Hydration Status / Q000235:genetics*; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic; D014556:Urine
C488034:ACE protein, human; D007703:Peptidyl-Dipeptidase A
Angiotensin-converting enzyme gene; Body cellular mass index; Body composition; Hydration; Phase angle; Urine specific gravity