SLOS Overview

Smith-Lemli-Optiz syndrome, in layman's terms, is the inability to correctly produce or synthesize cholesterol due to a low occurrence of the 7-DHC reductace enzyme. Cholesterol is an essential nutrient for every cell in a person's body. It is needed to develop and grow appropriately, thus the reason for developmental delay in those with SLOS. It is a metabolic genetic issue and is estimated that as many as 1 in 30 people are carriers for the syndrome. There is a wide range symptoms and degrees of health, but the majority of those with SLOS can live to adulthood given the proper treatment and careful monitoring for levels of sterol cholesterol and 7-DHC (the latter being the precursor to cholesterol production). Current treatment is to give cholesterol either in synthetic form, or via natural foods such as egg yolk and cream, or a combination of both. A short list of some of the major issues faced by those with SLOS are:

• heart, liver, or kidney problems
• low or extremely low muscle tone;delaying or inhibiting development and speech
• cleft palates or high palates
• oral aversions and feeding problems, often failure to thrive
• reflux, sometimes severe requiring surgery
• ptosis of the eyes, sometimes requiring surgery
• cateracts
• behavioral issues such as outbursts and self-abuse
• inability to sleepli>
• sensitivity issues to textures and environments
• constipation; sometimes with a secondary diagnosis of Hirshprungs Disease
• sensitivity to the sun
• communication problems; good receptive language abilities, but unable to communicate well
• hearing issues
• weaker immune systems
• scoliosis; brittle bones; osteoperosis
• allergies
• sporadic red cheeks, blueish nailbeds and lips
• small veins (hard to draw blood)

There are two ways to test for SLOS. A specialized blood test to measure the level of 7-DHC is the most common test. This test requires a standard blood draw and then the blood is sent to a lab that can do tandem mass-spectometery to break down the cholesterol into parts: sterol cholesterol, 7-DHC and 8-DHC. There are approximately a dozen labs in the United States that can perform this test including KKI, Baylor, Mayo clinc, OHSU, and Dr. Tint's lab. The second way to test is to have molecular testing (also known as DNA testing) done to look for the known SLOS mutations. This also requires a blood draw. Most families get the diagnosis of SLOS by way of the 7-DHC test and then have the DNA testing done so that they may inform family members who also may wish to be tested; especially those of child bearing age.