Table 6.

Age of onset of diabetes mellitus, optic atrophy, hearing loss, and diabetes insipidus based on genotype classification

Genotype	Diabetes mellitus (Mean ± SD)	Optic atrophy (Mean ± SD)	Deafness (Mean ± SD)	Diabetes insipidus (Mean ± SD)
Group 1	6.3 ± 3.5 years	11.7 ± 5.7 years	14.4 ± 7.2 years	13.9 ± 6.7 years
	n = 300	n = 249	n = 142	n = 114
Group 2	12.0 ± 9.9 years	15.8 ± 11.4 years	18.0 ± 13.7 years	18.0 ± 10.2 years
	n = 90	n = 81	n = 37	n = 29
P (t‐test)	<0.0001	0.0021	0.125	0.047

Notes: Group 1: variants predicted to cause complete or partial loss of function (N‐terminal nonsense and frameshifts, splice‐site variants predicted to cause exon skipping/deletions; C‐terminal nonsense and frameshift; N‐terminal small in‐frame deletions/duplications/insertions/indels); or compound heterozygous where one variant is predicted to cause complete and the other a partial loss of function.

Group 2: variants predicted to cause minor loss of function (missense, C‐terminal small in‐frame deletions/duplications/insertions/indels) or compound heterozygous for a variant predicted to cause partial and minor loss of function.