Structural genes of coagulation factors VII and X located on 13q34

From 7 cases of abnormalities involving chromosome 13, the structural gene(s) coding for coagulation factors VII and X were located in the region 13q34-13qter. Gene-dosage effects for these coagulation factors seem to act in both directions, causing a decrease when there is monosomy of segment 13q34, but also, as has not been demonstrated before, an increase when there is trisomy of this same segment.