Analysis artefacts of the INS-IGF2 fusion transcript

BMC Molecular Biology

Table 1 qPCR analysis of INS-IGF2, INS and IGF2

Cell type	Gene	cDNA input (ng)	C_t values					GAPDH normalized exp. Rel. To INS
Cell type	Gene	cDNA input (ng)	Prep1	Prep2	Prep 3	Mean	GAPDH norm	GAPDH normalized exp. Rel. To INS
Human islets	INS	0.05	20.5	18.9	20.4	19.9	−6.3	1
Human islets	INS-IGF2	0.05	No C_t	33.3	34.8	34.8	8.1	0.000046
Human islets	IGF2	0.05	32.8	32.7	31.3	32.3	6	0.000194
Human islets	GAPDH	0.05	26.9	27	24.9	26.2	0	–
EndoC-βH1	INS	5	14.8	14.3	14.4	14.5	−3	1
EndoC-βH1	INS-IGF2	5	29.9	30.8	28.3	29.7	12.2	0.000072
EndoC-βH1	IGF2	5	18.3	19.2	18.2	18.6	1.1	0.059678
EndoC-βH1	GAPDH	5	17.2	18.2	17.1	17.5	0	–

Relative expression of INS-IGF2, INS and IGF2 determined by qPCR for EndoC-βH1 cells and human islets. All mRNAs were analysed in 3 independent preparations, each in technical duplicate and the average of each duplicate is shown for each preparation (prep). GAPDH was used as input control. It is clear that INS-IGF2 is expressed at very low levels compared to Insulin, i.e. in the order of >20,000 fold less in human islets and 40,000 fold less in the human beta cell line EndoC-βH1.

ISSN: 1471-2199