Table 3 Potential contribution of TYR S192Y/R402Q haplotype to molecular diagnoses in OCA cohorts with missing heritability.

Phenotype

Nystagmus and/or albinism

OCA1

OCA1

Nystagmus and/or absence of fovea

Albinism (OCA, AROA or OA)

Nystagmus and at least one other ocular feature of albinism, no skin hypopigmentation

Country (ethnicity)

England

NA

(Iranian)

France

Scandinavia (Scandinavian)

England

Number of individuals in the cohort

51

3

6

158

29

4

Number of individuals hom or het for both TYR S192Y and R402Q, where S192Y/R402Q haplotype is possible

49

2

0

64

21

4

Number of individuals in whom it was possible to determine the phase of TYR S192Y, R402Q and pathogenic or likely pathogenic variants (“informative cohort”)

23

2

6

31

6

2

Number of individuals in whom TYR S192Y and R402Q were in cis, and in trans to pathogenic or likely pathogenic TYR variant in the informative cohort

23

2

0

31

6

2

The proportion of “informative cohort” where S192Y/R402Q haplotype is possible and molecular diagnoses due to TYR S192Y/R402Q haplotype in trans to pathogenic or likely pathogenic TYR variant

23/23 (100%)

2/2 (100%)

S192Y/R402Q haplotype not possible in any individuals in the study

31/31 (100%)

6/6 (100%)

2/2 (100%)

Combined proportion of “informative cohort” where molecular diagnoses are due to TYR S192Y/R402Q haplotype in trans to pathogenic or likely pathogenic TYR variant

64/64 (100%)

The proportion of cohort where molecular diagnoses due to TYR S192Y/R402Q haplotype in trans to pathogenic or likely pathogenic TYR variant

23/51 (45.1%)

2/3 (66.7%)

0/6 (0%)

31/158 (19.6%)

6/29 (20.7%)

2/4 (50%)

Combined proportion of cohort where molecular diagnoses are due to TYR S192Y/R402Q haplotype in trans to pathogenic or likely pathogenic TYR variant

64/251 (25.5%)