Table 2.

Location and Type of Somatic Mutations in Enlarged Leader Intron Hybrid Loci

Nucleotide		3ACPM2-23				4ACPM1-2						4ACPM1-3
		B2		G6		D9		G3		C6		D5		F1
Vector
1
3′ of Promoter
113						GTC→ GGC
116						CTC→ CAC
Leader intron
186										TAA→ TCA
202										GGT→ GCT
209								ATT→ AAT
Dros. intron
247														TAG→ TTG
249										CA→ CCA
263														TGT→ TCT
276		start Δ								TGT→ TAT
306		Δ												CAT→ CGT
324		Δ												TAC→ TCC
367		Δ
369		Δ						CAC→ CTC
375		Δ						AAC→ AGC						AAC→ AGC
391		Δ												GTA→ GAA
400		Δ												ATG→ AGG
414		Δ										GAA→ GCA
417		Δ						TAT→ TGT
427		Δ												AAG→ AGG
428		Δ				AGT→ AAT
431		Δ		TAT→ TTT
436		Δ												CTT→ CAT
441		Δ								AGT→ ACT
466		Δ												CA→ CCA
472		Δ												AGC→ AAC
479		Δ										GAT→ GGT
489		Δ										AAA→ ACA
509		Δ										AAT→ ATT
519		Δ												start Δ
520		Δ										TAA→ TGA		Δ
531		Δ								TAA→ TTA				Δ
565		Δ		GAT→ GGT										Δ
576		Δ										AGT→ AAT		Δ
579		Δ						AAT→ ACT						Δ
583		Δ		TAC→ TGC										Δ
592		Δ										TAT→ TTT		Δ
595		Δ		GTA→ GCA										Δ
613		Δ										TAT→ TCT		Δ
634		Δ		TAC→ TTC										Δ
638		Δ										TAA→ TGA		Δ
646		Δ				TAC→ TCC								Δ
Nucleotide		3ACPM2-23				4ACPM1-2						4ACPM1-3
		B2		G6		D9		G3		C6		D5		F1
701		Δ										TAT→ TTT		Δ
703		Δ										TAG→ TGG		Δ
705		Δ		GCA→ GTA										Δ
706		end Δ												Δ
712												AGC→ AAC		Δ
715												AAT→ AGT		Δ
721				AGC→ ATC										Δ
726				TTC→ TGC										Δ
734		TTA→ TAA												Δ
735				TAT→ TTT										Δ
751		TAA→ TGA												Δ
756				AAG→ AGG										Δ
763		TTA→ TAA												Δ
773		GCC→ GTC												Δ
776												AAG→ AGG		Δ
794		TTT→ TCT												Δ
826												CGT→ CTT		Δ
845						CGT→ CAT								Δ
855								AAT→ ATT						Δ
857				TTT→ TCT										Δ
860								TAT→ TTT				TAT→ TGT		Δ
868												AAG→ AGG		Δ
869														end Δ
905										TAT→ TGT		TAT→ TGT
926						GGT→ GAT
951 and 952				ACC→ ATT
954				CCT→ CAT
956												TAA→ TCA
968												AAT→ ATT
Leader intron
977				AAG→ AGG										AAG→ AGG
983				AAT→ ACT
1006														TCC→ TAC
FW 1
1068				AGC→ ACC
1079														GGC→ GAC
1110														GCT→ GTT
1114														CTG→ CAG
1119														TAT→ TTT
CDR 1
1132														GCT→ GTT
1139						TAT→ TTT								TAT→ TGT
1141						TAA→ TCA								TAA→ TGA
FW2
1152												AAA→ AGA
1183		TTG→ TAG
Nucleotide		3ACPM2-23				4ACPM1-2						4ACPM1-3
		B2		G6		D9		G3		C6		D5		F1
CDR2
1190														TAT→ TTT
1203												AAT→ AGT
1204				ATG→ AAG
1210				ATA→ ACA
1212		ACT→ ATT		ACT→ ATT										ACT→ ATT
1215												AAG→ ACG
1216														AGT→ ACT
FW3
1246														CAC→ CTC
1255				TAG→ TCG
CDR3
1357		ACT→ ATT
1368														TAC→ TCC
JH2-JH3
Intron
1479												TAT→ TTT
1595														TTA→ TCA
1597														ATA→ ACA
1694

The left hand column lists the nucleotide positions observed to be somatically mutated in the enlarged leader intron hybrid loci. Nucleotide 1 is 148 nucleotides 5′ of the initiation codon in the V_H leader exon. The sequenced region ends 199 bases 3′ of the VDJ. Various subregions of the hybrid loci are labeled at the beginning of each subregion. The mutations observed in each of the seven hybrid loci are shown below the hybridoma names. In each case the germline nucleotide triplet (or doublet in the case of the insertion mutations) is shown, as is the mutant nucleotide triplet, with the mutant base underlined. The beginning and end of the large continuous deletions present in two of the hybrid loci are indicated by “start Δ” and “end Δ” with all intervening nucleotide positions listed also indicated by “Δ”.