Table 1. Impact of the 14 bp InDel on the luciferase reporter gene expression when both construction types (1Fter-4R and 1Fter-2R primers) were considered in each cell line independently or in the four cell lines in combination.

	FON	JEG-3	M8	U251MG	F+J+M+U
Median 14 bp In	0.0832 (46)	0.0655 (36)	0.2957 (46)	0.1324 (36)	0.1246 (164)
Median 14 bp Del	0.2905 (62)	0.1213 (48)	0.3284 (56)	0.2045 (47)	0.2087 (213)
MW	P < 0.0001	P < 0.0001	P = 0.1149	P < 0.0001	P < 0.0001

MW: The two-tailed Mann-Whitney test was used to compare the haplotype group exhibiting the 14 bp insertion (UTR-2, UTR-5, and UTR-7) and the haplotype group having the 14 bp deletion (UTR-1, UTR-3, UTR-4, and UTR-18). Median Luciferase expression (RLU) is downregulated more intensively by UTRs with 14 bp insertion. (): number of experiments.