"...father of the affected, carries one copy of the CF-mutation 1717 (this mutation is found in Italian and Jewish CF chromosomes). (my father) also has an unusual pattern of exon 10 amplification. This exon (a coding segment of the CF gene) includes the mutations delta F-508 and delta I-507. His pattern resembles that expected for a carrier of delta F-508, but when the DNA is mixed with normal DNA, instead of producing a heterozygous pattern, it does not change in its migration. This likely represents a sequence variant, though it is possible that his CF-gene contains two mutated segments- 1717 and exon 10. We believe the variant change is included in the same gene because (me), the affected proband has inherited the delta F-508 mutation from his mother and both the 1717 and the variant exon 10 from his father."
That's quoted directly from the letter my parents and CF doc received from The New York Hospital-Cornell Medical Center back in 1992 when I was tested for CF. I don't know if it'll answer any of your questions but I just recently read this letter for the first time and it's the only thing I have read about my other mutation. I also have delta f-508 in addition to 1717-1g>a.
