A study conducted in 1998 found that congenital<unk>  tissues taken from some patients contained an acquired mutation, the ETV6-NTRK3 fusion gene. This gene results from a translocation of genetic material from the ETV6 gene located on the short arm (designated p) of chromosome 12 at position p13.2 (i.e. 12p13.2) to the NTRK3 gene located on the long arm (designated q) of chromosome 15 at position q25.3 (i.e. 15q25.3). This ETV6-NTRK3 gene fusion is notated as t(12;15)(p13;q25) and consists of the 5' end of ETV6 fused to the 3' end of NTRK3. In consequence, the chimeric protein product of this gene lacks ETV6 protein's transcription factor activity while having NTRK3 protein's tyrosine kinase in an unregulated and continuously active form. Either event can drive the malignant growth of cells but in most cases the chimeric protein's tyrosine kinase activity appears responsible for doing so. Based on a limited number of genetic studies (a total of 65 patients), the ETY6-NTRK3 fusion gene appears to occur in most cases of the cellular and some cases of the mixed but no cases of the classical types of congenital<unk> . However, a more recent study of 19 patients detected the fused gene in all 8 cases of cellular, 5 of 6 cases of mixed, and 0 of 5 cases of classic<unk> . This suggests that expression of this fused gene may be more common in cellar and mixed<unk>  than previously appreciated. Trisomy, i.e. pathological presence of an extra chromosome, also occurs in these neoplasms. Trisomy of chromosome 11 (e.g. trisomy 11) appears to be the most commonly found trisomy in this disease, being detected in 7 of 13 genetically studied cases. Individual case reports have also found trisomy 8 (9 cases), 17 (4 cases), 20 (4 cases), 7 (3 cases), 10 (3 cases), 18 (2 cases), 2 (2 cases), and 9 (2 cases) associated with the disease. The contribution of these trisomies to the development of<unk>  is unclear.
Mesoblastic nephroma
Cystic nephroma
Renal medullary fibroma
Medullary sponge kidney
Renal anaplastic sarcoma
Papillary renal cell carcinoma
Renal medullary carcinoma
Renal oncocytoma