There is a newer version of this record available.

Journal article Open Access

Dichromacy: Color Vision Impairment and Consanguinity in Heterogenous Population of Pakistan

Akhtar, Muhammad Shoaib; Aslamkhan, Muhammad; Zar, Mian Sahib; Hanif, Asif; Haris, Abdul Rehman


Background and Objectives: Dichromacy, an X-linked recessive disorder is identified worldwide, more in males than females. In European Caucasians, its incidence is 8% in males and 0.5% in females. In India, it is 8.73% in males and 1.69% in females, and in Iran, it is 8.18% in males and 0.43% in females. Population based epidemiological data about dichromacy in different ethnic groups in Pakistan is not available. The aim of this study was to find out the population prevalence of inherited red-green dichromacy in a heterogenous population of the district of Chiniot, Punjab, Pakistan, and to determine the impact of consanguinity and ethnicity.

Methods: In this cross-sectional study, boys and girls of the higher secondary schools were examined in the three tehsils of district Chiniot. Pseudoisochromatic Ishihara Test has been employed for detection of dichromacy in the study population. The sample size was calculated statistically as 260, which was expanded to 705 and divided by population density of the three tehsils.

Results: Screening of 359 males and 346 females revealed 19 (5.29%) dichromat males and only 2 (0.58%) females. The study population belonged to 23 castes / isonym groups. The consanguinity found in the district of Chiniot is 84.82% and in the dichromat families, it is 85.71%, of which 52.37% are first cousin.

Interpretation & Conclusion: The study has shown that the incidence of dichromacy could be reduced through genetic counseling

Files (1.5 MB)
Name Size
1.5 MB Download
All versions This version
Views 31676
Downloads 537142
Data volume 805.9 MB213.1 MB
Unique views 24159
Unique downloads 411134


Cite as