C = normal gene / non-cystinosis gene
c = recessive gene /cystinosis gene
Cc = carrier / heterozygote / no cystinosis
CC = non carrier / no cystinosis
cc = cystinosis
This is the pattern of autosomal recessive inheritance.
Carriers have normal
health. If two people who are carriers for the cystinosis gene have a child there is a :
- 1 in 4 chance the child will have cystinosis
(cc)
- 2 in 4 chance the child will not have cystinosis, but will be a carrier
(Cc,
cC)
- 1 in 4 chance the child will neither have cystinosis nor be a carrier
(CC)
- 2 in 3 chance that an unaffected/non-manifesting child will be a
carrier
(Cc+cC)
/ (Cc+cC+CC)