def get_transcripts(gene_id, isoforms_file):
    """Get transcript for gene."""
    transcripts = []
    f = open(isoforms_file, "r")
    for line in f:
        line_data = line.rstrip().split("\t")
        gene = line_data[0]
        trans = line_data[1]
        if gene == gene_id:
            transcripts.append(trans)
    f.close()
    return transcripts