diff --git a/sequence_extractor/exon_concatenation.py b/sequence_extractor/exon_concatenation.py
index 27f0c2a6d12fb7c391b29eadbcdd77b573749d4f..666c303a5007b95492fcb050e05fd40d81ec7be0 100644
--- a/sequence_extractor/exon_concatenation.py
+++ b/sequence_extractor/exon_concatenation.py
@@ -1,33 +1,3 @@
-def exon_concatenation_old(
-	filename: str
-) -> list:
-	"""Concatenates all sequences in fasta file with the same transcript ID header and then outputs a list containing sequence headers (Transcript ID) and sequences that have been concatenated.
-
-	Args:
-		filename: The name of the fasta file having multiple entries for the same transcript ID.
-
-	Returns:
-		A list with headers in the even indices and their corresponding sequences in the odd indices
-	"""
-	fa = open(filename,'r')
-	lines = fa.readlines()
-	to_write_to_file = []
-	for x in range(int(len(lines)/2)):
-		if x == 0:
-			annotation = lines[0][0:16]
-			read = lines[1][:-1]
-		if x >= 1:
-			if lines[2*x][1:16] == lines[2*(x-1)][1:16]:
-				read+= lines[(2*x)+1][:-1]
-			else:
-				to_write_to_file.append(annotation)
-				to_write_to_file.append(read)
-				annotation = lines[2*x][0:16]
-				read = lines[(2*x)+1][:-1]
-	to_write_to_file.append(annotation)
-	to_write_to_file.append(read)
-	return to_write_to_file
-
 def exon_concatenation(
 	post_bedtools_fasta: str
 ) -> list: