- A 1.9-Kb 5' fragment from the human COL1A1 gene drives inappropriate expression of the human COL2A1 gene in tissues of transgenic mice that normally express only the COL1A1 gene. Ala-Kokko, L., Yuan, C.M., Le Guellec, D., Franc, S., Fertala, A., Khillan, J.S., Sokolov, B.P., Prockop, D.J. Ann. N. Y. Acad. Sci. (1996)