The Wilms tumor suppressor gene 1, WT1, located on chromosome 11p13 is
mutated in only a subset of Wilms tumors. Cytogenetic studies of Wilm
s tumors show that the most frequent structural anomalies after those
affecting chromosome 11p are rearrangements of Iq, suggesting that the
re is a gene involved in Wilms tumor etiology in this region, The WT1
target sequence +P5 (D1S3309E), isolated using whole-genome polymerase
chain reaction (PCR), binds all WT1 isoforms in vitro and has been ma
pped to 1q21-22. As +P5 may mark a 1q Wilms tumor gene, constitutional
and tumor DNA from 33 Wilms tumor patients (36 tumors) was screened f
or allele imbalance using microsatellite markers from 1p21 to 1q44. Al
though no gross rearrangements of the +P5 region were found, this stud
y demonstrates allele imbalance for 1q in 12% of patients (5/36 tumors
), defining a smallest region of overlap at 1q21. This finding support
s a role for 1q21 in Wilms tumorigenesis. (C) Elsevier Science Inc., 1
997.