title: A study of consanguineous marriage as a risk factor for developing comitant strabismus.
abstract: Inheritance has an important role in the etiology of comitant strabismus. Consanguineous marriage is a leading factor in birth defects in which inheritance has a role. The aim of this study is to reveal if consanguineous marriage increases the risk of developing comitant strabismus. We included 461 patients who underwent primary surgery for comitant strabismus in Shiraz University Khalili Hospital (Fars province, southern Iran) between years 2003 and 2013 in our study. All the patients were living in Shiraz, Iran. Patients were categorized into the following 4 groups: (1) intermittent or constant exotropia, (2) infantile esotropia, (3) non-accommodative acquired esotropia, and (4) accommodative acquired esotropia. A total of 421 healthy children who were born in Shiraz, at the same period of time, were also studied as a control group. Presence and type of the consanguineous marriages were evaluated in the parents of the patients and control group by a questionnaire. Mean of inbreeding coefficient (α) was calculated in each group of patients and was compared with those of control group. The proportion of parental first cousin marriage was 37.7 and 23.5 % among patient and control groups. The mean of inbreeding coefficients (α) were 0.0236, 0.0283, 0.0288, and 0.0236 in four groups of the patients, respectively. The mean of inbreeding coefficient was 0.0263 in total patients, which was significantly higher than 0.0164 of control group (T = 5.27, df = 880, P < 0.001). Patients with non-accommodative acquired esotropia had the highest mean of inbreeding coefficient (α) (0.0288). It seems that recessive form of inheritance plays an important role in the etiology of comitant strabismus. Modified screening programs may be needed for earlier detection of strabismus in the offspring of consanguineous couples.
authors: Poostchi Eye Research Center, Department of Ophthalmology, Shiraz University of Medical Sciences, Zand Avenue, Shiraz, Iran.
authors: Mansooreh
authors: M
authors: Bagheri
authors: Majid
authors: M
authors: Farvardin
authors: Mostafa
authors: M
authors: Saadat
references: Ophthalmic Genet. 1994 Mar;15(1):1-18
references: 7953247
references: Br J Ophthalmol. 1990 Oct;74(10):589-94
references: 2285681
references: Eye (Lond). 2002 Sep;16(5):519-21
references: 12194061
references: Ophthalmology. 2011 Nov;118(11):2251-61
references: 21856012
references: Saudi J Ophthalmol. 2012 Jul;26(3):265-70
references: 23961004
references: Jpn J Ophthalmol. 2002 Jan-Feb;46(1):59-64
references: 11853715
references: Mol Vis. 2011;17:1997-2002
references: 21850174
references: Yan Ke Xue Bao. 1991 Sep;7(3):153-5
references: 1842370
references: J Community Genet. 2012 Jul;3(3):185-92
references: 22109912
references: AMA Arch Ophthalmol. 1952 Jan;47(1):1-20
references: 14884796
references: Mol Vis. 2011 Apr 19;17:971-6
references: 21541264
references: Ann Hum Biol. 2004 Mar-Apr;31(2):263-9
references: 15204368
references: Am J Med Genet. 1994 Jan 1;49(1):114-7
references: 7864918
references: J Pediatr Ophthalmol Strabismus. 2001 Mar-Apr;38(2):78-82
references: 11310711
references: Acta Med Okayama. 2003 Jun;57(3):109-16
references: 12908008
references: J Genet Couns. 2009 Feb;18(1):82-6
references: 18843527
references: Ophthalmologica. 1979;179(4):225-34
references: 548860