Analysis of mutations in alpha-actinin 4 and podocin genes of patients with chronic renal failure due to sporadic focal segmental glomerulosclerosis.
Although the pathogenesis of idiopathic focal segmental glomerulosclerosis (FSGS) may be heterogeneous, autosomal dominant and recessive forms of FSGS are recognized. Recently, mutations in alpha-actinin 4 (ACTN4) and podocin genes were reported in patients with such familial FSGS. However, whether mutations in ACTN4 and podocin genes are associated with sporadic FSGS has not been determined. In the present study, we clarified the relation between mutations in ACTN4 and podocin genes and sporadic FSGS. We analyzed these reported mutations in ACTN4 and podocin in five patients with chronic renal failure due to therapy-resistant FSGS by direct sequencing of polymerase chain reaction products of ACTN4 and podocin. We found a C to T transition at nucleotide 465 in the ACTN4 gene in all of patients, and a T to C transition at nucleotide 954 in exon eight of podocin gene in two of five patients, resulting in no amino acid substitutions. Other mutations were not found in ACTN4 and podocin genes. Our findings suggest that sporadic FSGS is a heterogeneous disease, since ACTN4 and podocin genes are not found in our patients with sporadic FSGS.
Komatsuda
Atsushi
A
Third Department of Internal Medicine, Akita University School of Medicine, Akita City, Akita, Japan. komatsud@med.akita-u.ac.jp
Wakui
Hideki
H
Maki
Nobuki
N
Kigawa
Akihiro
A
Goto
Hiroyuki
H
Ohtani
Hiroshi
H
Hamai
Keiko
K
Oyama
Yuhta
Y
Makoto
Hirokawa
H
Sawada
Ken-ichi
K
Imai
Hirokazu
H
D000185:Actinin / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D002648:Child; D005192:Family Health; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005923:Glomerulosclerosis, Focal Segmental / Q000150:complications* / Q000235:genetics*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D007564:Japan; D007676:Kidney Failure, Chronic / Q000209:etiology* / Q000235:genetics*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008840:Microfilament Proteins; D017354:Point Mutation / Q000235:genetics*; D017422:Sequence Analysis, DNA
C111453:ACTN4 protein, human; D005819:Genetic Markers; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D008840:Microfilament Proteins; C407223:NPHS2 protein; D000185:Actinin