[Sensitivity, specificity and predictive value of the genetic analysis of SLC3A1 gene variants used for the diagnosis of cystinuria among the spanish population].
OBJECTIVE
To test the clinical usefulness of the analysis of point mutations R452W, M467T, 114C > A, 231T > A, 1136 + 3delT and 1332 + 7T > C in the gene SLC3A1 as well as their possible haplotypes used for the diagnosis of cystinuria in the mediterranean spanish population.


METHODS
A total of 48 patients with cystinuria, 44 relatives without cystinuria, and 81 healthy controls were studied. A genetic analysis was conducted in order to identify variants in the gene SLC3A1. The sensitivity, specificity, and predictive value for each genetic variant and for the possible haplotypes were calculated.


RESULTS
The specificity of mutations M467T, R452W, and 231T > A used for the diagnosis of cystinuria in the general population or for the different subtypes of cystinuria in involved families, was higher than 90%; nevertheless, none of the analysed variants reached a sensitivity higher than 80%. In the study of haplotypes, the highest sensitivity was obtained with the haplotype CTTT (83.8%); however, its specificity and predictive value were low (20.6% and 53.4%, respectively).


CONCLUSIONS
The studied genetic variants did not show enough clinical usefulness.
Guillén
M
M
Unidad de Epidemiología Genética y Molecular, Departamento de Medicina Preventiva y Salud Pública, Universitat de València, Valencia. marisa.guillen@uv.es
Corella
D
D
Cabello
M L
ML
Saiz
C
C
Hernández-Yago
J
J
D026923:Amino Acid Transport Systems, Basic; D002352:Carrier Proteins / Q000235:genetics*; D003555:Cystinuria / Q000175:diagnosis / Q000235:genetics*; D004252:DNA Mutational Analysis; D006239:Haplotypes; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics*; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012680:Sensitivity and Specificity; D013030:Spain
D026923:Amino Acid Transport Systems, Basic; D002352:Carrier Proteins; D008562:Membrane Glycoproteins; C499489:SLC7A9 protein, human