Days Set Up
Varies; test performed once per week
Analytic Time

2 - 8 days

MiChart Code
Smith/Lemli/Opitz (7-DHC & 8-DHC)(Sendout)
Soft Order Code

Test Updated:


8-Dehydrocholesterol (8-DHC)
7-Dehydrocholesterol (7-DHC)
SLO (Smith-Lemli-Opitz) Syndrome
Smith-Lemli-Opitz Screen,Plas.

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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

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Test Overview

Test Methodology

Gas Chromatography/Mass Spectrometry (GC/MS)

Test Usage

Diagnosis of Smith-Lemli-Opitz syndrome (7-dehydrocholesterol reductase deficiency).

Reference Range


* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Offsite

Collect specimen in a green top tube from a fasting patient (12 hour fast or just before next feeding for infants). Centrifuge, aliquot serum into a plastic vial within 45 minutes of collection and freeze.

Normal Volume
0.5 mL plasma
Minimum Volume
0.2 mL plasma

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.