Table 1.

Polymorphic repeat sequences of the ILPR with their corresponding transcriptional activity

Polymorphic repeat	Sequence	Transcriptional activity, %
a	ACA GGGG TGT GGGG	100
b	ACA GGGG TCT GGGG	30.0  ± 0.4
Variant b	AGA GGGG TCT GGGG	99.90  ± 0.04
c	ACA GGGG TCCT GGGG	20.0  ± 0.4
Variant c	AGGA GGGG TCCT GGGG	100.00  ± 0.004

“Restored” nucleotides are marked in bold-face. Constructs for the transfection studies were made by cloning a synthetic oligonucleotide containing four tandem copies of the corresponding polymorphic repeats upstream of the minimal prolactin-luciferase construct, Prl-luc. The transcriptional activity was determined in HeLa cells transfected in the absence and presence of a Pur-1 expression vector driven by a cytomegalovirus (CMV) promoter as described (19). Transcriptional activities of the a repeat are set arbitrarily at 100% as described in ref. 22.