Heritabilities of ocular biometrical traits in two croatian isolates with extended pedigrees.
OBJECTIVE
To assess the effects of body stature and years of education, in addition to age and sex, on six oculometric traits and to estimate the heritabilities of these quantitative traits in two Croatian cross-population studies.


METHODS
Adult subjects living on the two Croatian islands of Vis and Korcula were recruited for a large epidemiologic and genetic study that included eye biometry, keratometry, and autorefraction. Effects and heritabilities were estimated by using general linear mixed models for axial length (AL), anterior chamber depth (ACD), corneal curvature (CC), corneal thickness (CT), lens thickness (LT), and spherical equivalent refraction (SER). Both cohorts were genotyped with dense SNP arrays, allowing the use of kinship coefficients derived from genotypic data (realized kinship) rather than from pedigree information (expected kinship).


RESULTS
Across cohorts, body mass index (BMI) did not consistently influence any of the ocular traits adjusted for age and/or sex, whereas height and years in education (YrEd) did, explaining up to an additional 5% of the variance (in CC). CT was the trait least influenced by covariates. Estimated heritabilities in Vis and Korcula, respectively, were 84% and 52% for CC, 75% and 71% for CT, 37% and 32% for LT, 59% and 45% for ACD, 37% and 74% for AL, and 0% and 17% for SER.


CONCLUSIONS
While heritabilities of CT and CC seemed uniformly high across studies of Caucasian datasets, estimates for SER varied widely and were at the lower end of the spectrum of published observations in our study.
Vitart
Veronique
V
MRC (Medical Research Council) Human Genetics Unit, IGMM (Institute of Genetics and Molecular Medicine), Edinburgh, Scotland, United Kingdom. v.vitart@hgu.mrc.ac.uk
Bencić
Goran
G
Hayward
Caroline
C
Herman
Jelena Skunca
JS
Huffman
Jennifer
J
Campbell
Susan
S
Bućan
Kajo
K
Zgaga
Lina
L
Kolcić
Ivana
I
Polasek
Ozren
O
Campbell
Harry
H
Wright
Alan
A
Vatavuk
Zoran
Z
Rudan
Igor
I
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000867:Anterior Chamber / Q000033:anatomy & histology; D001699:Biometry; D001827:Body Height / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D003315:Cornea / Q000033:anatomy & histology; D017523:Croatia; D005123:Eye / Q000033:anatomy & histology*; D005260:Female; D005838:Genotype; D006801:Humans; D007908:Lens, Crystalline / Q000033:anatomy & histology; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D019655:Quantitative Trait, Heritable; D012029:Refraction, Ocular / Q000502:physiology*; D055815:Young Adult