diff --git a/pyGeno/Chromosome.py b/pyGeno/Chromosome.py
index fb79600..b0baf34 100644
--- a/pyGeno/Chromosome.py
+++ b/pyGeno/Chromosome.py
@@ -72,12 +72,23 @@ def getSequenceData(self, slic) :
 				if sequenceModifier.__class__ is SF.SequenceDel :
 					seqPos = seqPos + sequenceModifier.offset
 					#To avoid to change the length of the sequence who can create some bug or side effect
-					data[seqPos:(seqPos + sequenceModifier.length)] = [''] * sequenceModifier.length
+					if (sequenceModifier.indel == 0):
+						data[seqPos:(seqPos + sequenceModifier.length)] = [''] * sequenceModifier.length
+					else: # indel
+						data[seqPos] = sequenceModifier.bases
+						seqPos += 1
+						data[seqPos:(seqPos + sequenceModifier.indel)] = [''] * sequenceModifier.indel
+
 				elif sequenceModifier.__class__ is SF.SequenceSNP :
 					data[seqPos] = sequenceModifier.alleles
 				elif sequenceModifier.__class__ is SF.SequenceInsert :
 					seqPos = seqPos + sequenceModifier.offset
-					data[seqPos] = "%s%s" % (data[seqPos], sequenceModifier.bases)
+					if (sequenceModifier.indel == 0):
+						data[seqPos] = "%s%s" % (data[seqPos], sequenceModifier.bases)
+					else: # indel
+						data[seqPos] = sequenceModifier.bases
+						seqPos += 1
+						data[(seqPos):(seqPos + sequenceModifier.indel)] = [''] * sequenceModifier.indel
 				else :
 					raise TypeError("sequenceModifier on chromosome: %s starting at: %s is of unknown type: %s" % (self.chromosome.number, snp.start, sequenceModifier.__class__))
 
diff --git a/pyGeno/SNPFiltering.py b/pyGeno/SNPFiltering.py
index b1694b0..bd778b8 100644
--- a/pyGeno/SNPFiltering.py
+++ b/pyGeno/SNPFiltering.py
@@ -29,16 +29,18 @@ def __init__(self, bases, sources = {}, ref = '-') :
 		Sequence_modifiers.__init__(self, sources)
 		self.bases = bases
 		self.offset = 0
+		self.indel = 0
 
 		# Allow to use format like C/CCTGGAA(dbSNP) or CCT/CCTGGAA(samtools)
 		if ref != '-':
 			if ref == bases[:len(ref)]:
 				self.offset = len(ref) 
 				self.bases = self.bases[self.offset:]
-				#-1 because if the insertion are after the last nuc we go out of table
+				#-1 because if the insertion are after the last nuc we go out of table	
 				self.offset -= 1
-			else:
-				raise NotImplemented("This format of Insetion is not accepted. Please change your format, or implement your format in pyGeno.")
+			# Allow indel like GG/GAG
+			else: 
+				self.indel = len(ref) - 1
 
 
 class SequenceDel(Sequence_modifiers) :
@@ -47,6 +49,7 @@ def __init__(self, length, sources = {}, ref = None, alt = '-') :
 		Sequence_modifiers.__init__(self, sources)
 		self.length = length
 		self.offset = 0
+		self.indel = 0
 
 		# Allow to use format like CCTGGAA/C(dbSNP) or CCTGGAA/CCT(samtools)
 		if alt != '-':
@@ -54,8 +57,10 @@ def __init__(self, length, sources = {}, ref = None, alt = '-') :
 				if alt == ref[:len(alt)]:
 					self.offset = len(alt)
 					self.length = self.length - len(alt)
+				# Allow indel like  CATA/CAA
 				else:
-					raise NotImplemented("This format of Deletion is not accepted. Please change your format, or implement your format in pyGeno.")
+					self.bases = alt
+					self.indel = len(ref) - 1
 			else:
 				raise Exception("You need to add a ref sequence in your call of SequenceDel. Or implement your format in pyGeno.")