SCGB2A1 and ductal breast carcinoma in situ: High expression of SCGB2A1 was frequently associated with high expression of SCGB2A2 and SCGB1D2, encoding Mammaglobin A and lipophilin B. Expression differences at both the RNA and protein level of SCGB1D2 have also been observed in a prior study of 24 patients, comparing DCIS with and without progression to IDC5.