Familial renal glucosuria: a clinicogenetic study of 23 additional cases.
BACKGROUND
Familial renal glucosuria (FRG) is an inherited renal tubular disorder characterized by persistent isolated glucosuria in the absence of hyperglycemia that is caused by mutations in the sodium-glucose cotransporter SGLT2 coding gene, SLC5A2.


OBJECTIVE
We conducted molecular and phenotype analyses of a cohort of 23 unrelated Korean children with FRG.


METHODS
Mutational analysis of the SLC5A2 gene was conducted in this multicenter study organized by the Korean Society of Pediatric Nephrology.


RESULTS
A total of 21 different SLC5A2 mutations were detected, including 19 novel mutations. All patients had at least one mutated allele; ten patients had homozygous or compound heterozygous mutations and 13 patients had a single heterozygous mutation. Most mutations were private. Patients with two mutations were diagnosed earlier with larger amounts of urinary glucose excretion than patients with single mutations. Pedigree analysis data were consistent with the inheritance of a codominant trait with incomplete penetrance.


CONCLUSIONS
These findings extend the allelic heterogeneity in FRG and confirm previous observations of inheritance and genotype–phenotype correlation in patients with this disease.
Department of Pediatrics, Seoul National University Children’s Hospital, 101 Daehak-Ro, Jongno-Gu, Seoul 110-744, Korea.
HyunKyung
H
Lee
Kyoung Hee
KH
Han
Hye Won
HW
Park
Jae Il
JI
Shin
Chan Jong
CJ
Kim
Mee Kyung
MK
Namgung
Kee Hyuck
KH
Kim
Ja Wook
JW
Koo
Woo Young
WY
Chung
Dae-Yeol
DY
Lee
Su-Yung
SY
Kim
Hae Il
HI
Cheong
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006030:Glycosuria, Renal / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007223:Infant; D007723:Korea; D008297:Male; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D051297:Sodium-Glucose Transporter 2 / Q000235:genetics*
D051297:Sodium-Glucose Transporter 2