TITLE:
Unusual Detection of Lathosterol in Amniotic Fluids Investigated for the Determination of Cholesterol and 7-Dehydrocholesterol for Suspected Smith-Lemli-Opitz Syndrome
AUTHORS:
Veniero Gambaro, Fiorenza Farè, Andrea Barlocco, Federico Maggi, Giuseppe Simoni, Lucia Dell’Acqua, Chiara Rusconi, Gabriella Roda
KEYWORDS:
Lathosterol; Cholesterol; SLO Syndrome; Amniotic Fluid; GC/FID; GC/MS
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.5 No.4,
March
13,
2014
ABSTRACT: The Smith-Lemli-Opitz syndrome (SLOS), is an autosomal recessive disorder caused by a 7-dehydrocholesterol reductase deficiency, which is characterized by abnormally elevated amniotic fluid 7-DHC (7-dehydrocholesterol) concentrations. A GC/FID (gas-chromatography with a flame ionization detector) and GC/MS (gas-chromatography with a mass detector) method was optimized for the detection of cholesterol and 7-DHC in amniotic fluids. The quantitative determination of cholesterol in 39 control amniotic fluids evidenced that between the fourth and fifth month of pregnancy the levels of this analyte are quite constant, the concentration of total and free cholesterol being respectively 10.3 μg·mL﹣1 (SD = ±3.6) and 1.7 μg·mL﹣1 (SD = ±0.91), while the analysis of 60 amniotic fluids potentially related to SLOS, showed a higher variability of cholesterol levels. Moreover, in 13 samples an analyte which did not correspond either to cholesterol or to 7-DHC was detected. A GC/MS investigation allowed us to identify this compound as lathosterol, a precursor of cholesterol in the biosynthetic pathway.