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This 11-year-old boy has very light skin, white hair, and light blue eyes. Both of his parents and two siblings, a brother and a sister, have skin that is fairly dark. The boy is bothered by bright sunlight and his skin burns easily in the sun. He has nystagmus and visual acuity reduced to 20/100 best corrected with glasses of OD -7.00, OS -8.00 as well as 35 prism diopters of exotropia.

1.	The condition that this boy has is likely to have been inherited as:
	b -- autosomal recessive This condition, oculocutaneous albinism, is transmitted as an autosomal recessive trait.
2.	Tests to confirm the diagnosis or learn more about this condition include:
	e -- all of the above All of these tests could be useful.  The skin or hair bulb biopsy would determine the presence of tyrosinase.  Iris transillumination shows the lack of iris pigment. The fundus examination shows the lack of pigment and macular hypoplasia, and visual acuity testing tells what the patient can see.
3.	Which of the following would be most likely to help this boy?
	d -- an asymmetrical four muscle recession In a case like this, there is not a lot that can be done medically.  But, since the boy has both exotropia and nystagmus, an asymmetrical four muscle recession could be of some help in improving alignment and damping the nystagmus.  In a case like this, the lateral rectus muscles could be recessed 9.0 or 10.0 mm and the medial rectus muscles recessed 2.0 mm.   You can learn more about eye muscle surgery for nystagmus by going to Binocular Vision and Ocular Motility and/or Surgical Management of Strabismus, both in E-Resources on this site.