Association between polymorphisms of the atrial natriuretic peptide gene and proteinuria: a population-based study.
OBJECTIVE
In case-control studies, polymorphisms at the atrial natriuretic peptide gene (ANP) locus have been associated with presence of albuminuria in Type 1 and Type 2 diabetes. We evaluated the relationship between the ScaIand BstxI polymorphisms and albuminuria in the general population of the Mexico City Diabetes Study.


METHODS
Allele/genotype frequencies were analysed by PCR-RFLP analysis using ScaI (wild, A(2) vs mutated, A(1)) and BstxI (wild, C(708) vs mutated, T(708)) enzyme.


RESULTS
Among 1288 subjects, hypertension was present in 112 subjects, Type 2 diabetes in 191 and impaired glucose tolerance in 136; microalbuminuria was present in 464 subjects, and clinical proteinuria in 199. General frequencies were 0.93 and 0.96 for the wild alleles, and 0.07 and 0.04 for the mutated alleles, respectively for ScaI and BstxI. Frequency of A(1)was 0.08 in normoalbuminuric, 0.05 in microalbuminuric, and 0.05 in proteinuric patients (chi(2)=7.3, p=0.025). Frequency of T(708) was 0.06 in normoalbuminuric and 0.03 microalbuminuric and 0.03 in proteinuric subjects (chi(2)=8.1, p=0.017). By multivariate analysis, the associations between A(1)or T(708) allele and albuminuria were independent of age, sex, BMI, diabetes, and hypertension, (odds ratio (OR) 0.60, p=0.01, (OR) 0.51, p=0.004, respectively).


CONCLUSIONS
In the general population of Mexico City, both polymorphisms of ANP are associated with albuminuria independently of hypertension, and could play a role in protecting subjects against development of albuminuria.
Nannipieri
M
M
Department of Internal Medicine, University of Pisa, Pisa, Italy. nannipi@ifc.cnr.it
Posadas
R
R
Williams
K
K
Politi
E
E
Gonzales-Villalpando
C
C
Stern
M P
MP
Ferrannini
E
E
D000328:Adult; D000419:Albuminuria / Q000453:epidemiology / Q000235:genetics; D000483:Alleles; D009320:Atrial Natriuretic Factor / Q000235:genetics*; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D018149:Glucose Intolerance / Q000235:genetics; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000235:genetics; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D011153:Population; D011507:Proteinuria / Q000453:epidemiology / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D009320:Atrial Natriuretic Factor; C047020:endodeoxyribonuclease ScaI; C047564:CCANNNNNNTGG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific