Detection of CFTR Genotype and Evaluation of Clinical
Parameters in Siblings
As a result of DNA sequencing, the CFTR genotype of siblings were
identified as follows: Family 1, F1-P1, F1-P2, F508del/G85E (Class II);
Family 2, F2-P1, F2-P2, F508del/F508del (Class II); Family 3, F3-P1,
F3-P2, F3-P3, I1234V/I1234V (Class IV). Siblings in family 1 were
evaluated for pulmonary findings, hepatic involvement and other comorbid
conditions. 16-year-old F1-P2 had CFRD and severe hepatic involvement
with cirrhosis and waiting for liver transplantation but 12-year-old
F1-P1 had mild hepatic involvement and was not diagnosed with CFRD
during his follow-up. For this reason, F1-P2 was found to have severe
phenotype and F1-P1 to have mild phenotype. In family 2, siblings were
evaluated for pulmonary findings and hepatic involvement. Younger
sibling F2-P2 had severe hepatic involvement with chronic liver disease,
recurrent lung infections and severe pulmonary disease compared with
F2-P1. Therefore, F2-P2 was evaluated as severe and F2-P1 as mild
phenotype. Siblings in family 3 were evaluated for recurrent lung
infections, pulmonary function tests and severity of pulmonary disease.
According to pulmonary findings F3-P1 was evaluated to be mild, F3-P2
intermediate and F3-P3 who died due to respiratory insufficiency had
severe phenotype.