Eyelid Measurement In 7 Sub-ethnic Groups Of Malay: A Potential Parameter For Identification Of Ethnicity

Liza-Sharmini AT, Nur-Ayuni CZ, Bakiah S, Zilfalil BA

Purpose:
To determine and compare the ocular characteristics of seven Malay sub-ethnic groups residing in Peninsular Malaysia.

Methods:
A cross sectional population based study was conducted involving 185 healthy subjects (370 eyes) from 7 sub-ethnic groups between 17 to 49 years old. Those with systemic or ocular diseases were excluded. Ocular parameters include vertical fissure height (VFH), eyelid to eyebrow measurement, margin-reflex distance, eyelid crease, upward slanting of the lateral canthal, interpalpebral distance and exopthalmometer measurement. Ten mililiters of blood was obtained for microarray analysis using Affymetric 100K chip.

Results:
Analysis was done using One-Way Anova and followed by post hoc analysis. There was a statistical significant difference in most of ocular parameter between 7 sub ethnic groups of Malay (34 Kelantanese, 28 Javanese, 33 Bugis, 16 Champa, 23 Rawa, 32 Banjar and 38 Kedahan). There was significant difference of the distance of upper eyelid to eyebrow subethnic groups with Javanese has the highest upper eyelid to eyebrow distance (p=0.001). Javanese also has the highest degree of upward slanting of the lateral canthal (p<0.001). VFH also shown significant difference (p>0.001) between subethnic groups with Rawa has the highest VFH, highest marginal reflex distance and exophthalmometer measurement. Javanese has the highest component of markers belong to Chinese decent and Kelantanese and Kedahan have almost similar component markers belong to Indian decent based on microarray analysis.

Conclusion:
Malays is considered as one major ethnic group. However, they differ according to their historical decent. Eyelid parameters may play a role in differentiating their features.