Table 1. Sequence composition of >1 nucleotide CSR insertions.

	Sμ (J00440)	Insertion	Sγ (D78344)		Homology
	Polq WT
4648:4677	GGGACCCAGGCTttGAAGGCAATCCTGGGA	GCACTTC	GTACTTATAGAGGAACAGGGGCAGcgTAGA	2888:2917
5161:5190	ACTGTAATGAACTGGAATGAGCTGGGCCGC	CCT	GGAAATCAGGACAGGTACAAGcGTGTGGAT	7925:7954
5291:5320	TTCTGAGCTGAGATGAGCTGGaGTGAGCTC	TTACC	GGTAGCTATAGGGAATACAGAACAGGTGGG	2653:2682
4974:5003	GAAGGCgAGACTCATAAAGCTTGCTGAGCA	CCAGGACA	CCCTGTAGGGTAGCTGTAGGGAAATCAGGA	7906:7935	Sγ2278:2285
5206:5235	TGGCTTAACCGAGATGAGCCAAACTGGAAT	CCC	GAATAGCTACAGGGGAGCCAGGAGAGGTAG	2753:2782
4891:4920	AATTGAGAAAGAATAGAGACCTGCAGTTGA	TC	CTGATGGCAAATGGAAGGGCAGAGACCCAG	2957:2986
5110:5139	AGGTGATTACTCTGAGGTAAGCAAAGCTGG	CA	CCAGGTCTGCAGCTACATACGGGTAAGCAG	2694:2723
5297:5326	GCTGAGATGAGCTGGGGTGAGCTCAGCTAT	TT	TATAGGGAGCCAGGACAGGTGGAAGTGTGG	7602:7631
4667:4696	CAATCggGGGATTCTGGAAGAAAAGATGTT	CC	GGATCAAGGCAGAACAGGTCCAGGGGTGCC	2840:2869
	Polq WT+NU7026
5432:5461	TAGGGTGAGCTGAGCTGGGTGAGCTGAGCT	CCCAGT	AGTGTGGGGATCCAGGTAAGGCTGGACTGG	8264:8293
4620:4649	TGGAAGCTAATTTAGAATCAAGTAAGGAGG	CAAGACAGGTGG—GTGTGGGGATCAAGG	AGGAGAAATGGAAGAATGCAGATTCCAAAC	8030:8059	Sγ2820:2848
4907:4936	AGACCTGCAGTTGAGGCCAGCAGGTCGGCT	ACTA	TGGAACTGTGGGGACCCTGTAGGGTAGCTG	7892:7921
4787:4816	GTTGTTAAAGAATGGTATCAAAGGACAGTG	CTAgAAcGTAcT	TCAAGGCAGAACAGGTCCAGGGGTGCCAGG	2843:2872	Sμ3545:3556
5231:5260	GGAATGAACTTCATTAATCTAGGTTGAATA	GGTGGAAGTGTGGGG	AGGGCAGCCAGGACAGGTGGAAATGTGGTG	7750:7779	Sγ4882:4896
4879:4908	ACAGCTGTACAGAATTGAGAAAGAATAGAG	TGGGG—AGCTCAGCTATGCTAC-CGTGTTG-GG	CAGGAAGAATAGCTACAGGGGAGCCAGGAG	2747:2776	Sμ5309:5342
5291:5320	TTCTGAGCTGAGATGAGCTGGaGTGAGCTC	TTACC	GGTAGCTATAGGGAATACAGAACAGGTGGG	2653:2682
4974:5003	GAAGGCgAGACTCATAAAGCTTGCTGAGCA	CTACGACA	CCCTGTAGGGTAGCT GTAGGGAAATCAGGA	7906:7935
5237:5266	AACTTCATTAATCTAGGTTGAATAGAGCTA	GAC—GTaGCATTGTGTGacTC	CAGGCACAGTAGCTATAGGGGaGCCAAGAC	2796:2825	Sγ2575:2596
4989:5018	AAAGCTTGCTGAGCAAAATTAAGGGAACAA	TTGAG	TGAGGCAGGTAAGAGTGTGGGAACCCAGTC	8429:8458
5245:5274	TAATCTAGGTTGAATAGAGCTAAACTCTAC	AGTGCAGA	TGAGGCAGGTAAGAGTGTGGGAACCCAGTC	8429:8458	Sγ8821:8828
4685:4714	AGAAAAGATGTTTTTAGTTTTTATAGAAAA	GTAAT	TATAGGGGaGCCAAGAaAGGTGGAAGTGTG	2809:2838
4796:4825	GAATGGTATCAAAGGACAGTGCTTAGATCC	GAGGTGAGTGTGAGAGGACA AA	AAGTTtAGTAgTTATAGAGGAACAGGGGCA	2881:2910	Sμ4827:4845
5088:5117	GCTTCTAAcATGCGCTAAACTGAGGTGATT	CCAAGGACCCAGGCAGAGCAGCTCCAG TAGGCCA	CAAtcACAAGGGAACTGATGGCAAATGGAA	2943:2972	Sγ4014:4035
4663:4692	AAGGCAATCtTGGGATTCTGGAAGAAAAGA	CCAT	GAAGTGTAGTGACCCttGAAGAATAGCTAC	2733:2762
5002:5031	CAAAATTAAGGGAACAAGGTTGAGAGCCCT	TC	GGAATTGTGGTGACCCAGACAAAACAGCTA	7817:7846
4684:4713	AAGAAAAGATGTTTTTAGTTTTTATAGAAA	CC	ACAGGGAAGCTATAttAAAACCAGGACAcG	8132:8161
5133:5162	AAGCTGGGCTTGAGCCAAAATGAAGTAGAC	GC	TGGAAGGGCAGAGACCCAGACTAAATGGCT	2968:2997
5210:5239	TTAACCGAGATGAGCCAAACTGGAATGAAC	TA	AAAACCAGGACAGGAGGAAGAATGGGGATC	8148:8177
4816:4845	GCTTAGATCCgAGGTGAGTGTGAGAGGACA	AA	AAGTTtAGTAgTTATAGAGGAACAGGGGCA	2881:2910
4897:4926	GAAAGAATAGAGACCTGCAGTTGAGGCCAG	TT	AGGGTGTGGATCCAGGCAGGGTAGCTATAG	2634:2663
	Polq KO
5360:5389	AGCTACTCTGGAGTAGCTGAGATGGGGTGA	TT	CAAATGGAAGGGCAGAGACCCAGACTAAAT	2964:2993

30 bases flanking each side of the insertion are shown. The numbers separated by colons give the position relative to the beginning of the Sμ and Sγ genomic sequences. New mutations (different from the reference sequence) are shown in lower case. For some longer insertions (indicated in bold), homologies were identified in the switch region, at the positions indicated in the right column. Microhomologies at the junction site are underlined. A dash (-) indicates a base deletion. Sequences (graphed in Figure 4E) are from Polq ^+/+ (WT) and Polq ^−/− (KO) splenic B cells that were treated with NU7026 or mock-treated.