```r
library(BSgenome.Hsapiens.UCSC.hg19)
genome <- BSgenome.Hsapiens.UCSC.hg19
tx_seq <- extractTranscriptSeqs(genome, brca1cds)
tx_seq
```

```
##   A DNAStringSet instance of length 20
##      width seq                                         names               
##  [1]  2280 ATGGATTTATCTGCTCTTCG...TCCCCCACAGCCACTACTGA uc010whl.2
##  [2]  5379 ATGAGCCTACAAGAAAGTAC...TCCCCCACAGCCACTACTGA uc002icp.4
##  [3]   522 ATGGATGCTGAGTTTGTGTG...TCCCCCACAGCCACTACTGA uc010whm.2
##  [4]  2100 ATGGATTTATCTGCTCTTCG...GCAATTGGGCAGATGTGTGA uc002icu.3
##  [5]  5451 ATGCTGAAACTTCTCAACCA...TCCCCCACAGCCACTACTGA uc010cyx.3
##  ...   ... ...
## [16]  4095 ATGGATTTATCTGCTCTTCG...AAAGCATGGATTCAAACTTA uc010cyy.1
## [17]  4095 ATGGATTTATCTGCTCTTCG...AAAGCATGGATTCAAACTTA uc010whs.1
## [18]  3954 ATGCTGAAACTTCTCAACCA...AAAGCATGGATTCAAACTTA uc010cyz.2
## [19]  4017 ATGGATTTATCTGCTCTTCG...AAAGCATGGATTCAAACTTA uc010cza.2
## [20]  3207 ATGAATGTAGAAAAGGCTGA...AAAGCATGGATTCAAACTTA uc010wht.1
```