[Distribution of DRD4 and DAT1 alleles from dopaminergic system in a mixed Chilean population].
BACKGROUND
Genes for dopamine receptor DRD4 and dopamine transporter DAT1 are highly polymorphic. Two alleles of these genes, namely the DRD4.7 and the DAT1*9 are frequently associated to the attention deficit disorder with hyperactivity. In Europe, the allele for DRD4 receptor with four repetitions (DRD4.4) has the highest frequency, with a median of 69%, followed by DRD4.7, with a frequency of 15%. South American indigenous populations have higher frequencies for DRD4.7 (61%) than for DRD4.4 (29%). The ten repetition allele for DAT1 transporter has a high frequency among Europeans (72%) and Amerindians (100%). The allele DAT1*9 is the second most frequent allele.


OBJECTIVE
To study the frequency of DRD4 and DAT1 alleles in a Chilean population sample.


METHODS
One hundred serum samples were obtained from blood donors in two public hospitals in Santiago. Polymorphic regions for DRD4 and DAT1 were amplified by polymerase chain reaction.


RESULTS
The allele DRD4.4 had a frequency of 59% and DRD4.7 a frequency of 27%. The allele DAT1*10 had a frequency of 74%, followed by DAT 1*9, with a frequency of 23%.


CONCLUSIONS
In a Chilean population sample, the frequency of DRD4 and DAT1 alleles was very similar to that of European populations.
Vieyra
Gonzalo
G
Programa de Genética Humana, ICBM, Facultad de Medicina, Universidad de Chile, Casilla 70061, Santiago 7, Chile.
Moraga
Mauricio
M
Henríquez
Hugo
H
Aboitiz
Francisco
F
Rothhammer
Francisco
F
D000483:Alleles; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics*; D002677:Chile; D050483:Dopamine Plasma Membrane Transport Proteins; D005787:Gene Frequency; D005828:Genetics, Population; D006801:Humans; D007199:Indians, South American / Q000235:genetics; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000235:genetics*; D009419:Nerve Tissue Proteins; D016133:Polymerase Chain Reaction; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D050638:Receptors, Dopamine D4
C493599:DRD4 protein, human; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D017448:Receptors, Dopamine D2; C493214:SLC6A3 protein, human; D050638:Receptors, Dopamine D4
Distribución de alelos de los genes DRD4 y DAT1 del sistema dopaminérgico en la población mixta de Santiago de Chile.