CHEK2 and 22q11.2 deletion syndrome: A literature search did not show a direct link between CHEK2 and the eye, however one study reported mapping of a locus on chromosome 22q12.1–q13.1 (OPA5) to autosomal dominant optic atrophy [40] and one case-report described an association of chromosome 22q11.2 deletion syndrome with optic disc swelling, which is probably caused by the resulting hypocalcaemia [41].