Simple Sequence Repeats in the National Longitudinal Study of Adolescent Health: An Ethnically Diverse Resource for Genetic Analysis of Health and Behavior

Simple sequence repeats (SSRs) are one of the earliest available forms of genetic variation available for analysis and have been utilized in studies of neurological, behavioral, and health phenotypes. Although findings from these studies have been suggestive, their interpretation has been complicated by a variety of factors including, among others, limited power due to small sample sizes. The current report details the availability, diversity, and allele and genotype frequencies of six commonly examined SSRs in the ethnically diverse, population-based National Longitudinal Study of Adolescent Health. A total of 106,743 genotypes were generated across 15,140 participants that included four microsatellites and two di-nucleotide repeats in three dopamine genes (DAT1, DRD4, DRD5), the serotonin transporter, and monoamine oxidase A. Allele and genotype frequencies showed a complex pattern and differed significantly between populations. For both di-nucleotide repeats we observed a greater allelic diversity than previously reported. The availability of these six SSRs in a large, ethnically diverse sample with extensive environmental measures assessed longitudinally offers a unique resource for researchers interested in health and behavior.     

Identification of the designer steroid Androsta‐3,5‐diene‐7,17‐dione in a dietary supplement

A liquid chromatography‐mass spectrometry (LC–MS) screen for known anabolic‐androgenic steroids in a dietary supplement product marketed for “performance enhancement” detected an unknown compound having steroid‐like spectral characteristics. The compound was isolated using high performance liquid chromatography with ultraviolet detection (HPLC–UV) coupled with an analytical scale fraction collector. After the compound was isolated, it was then characterized using gas chromatography with simultaneous Fourier Transform infrared detection and mass spectrometry (GC–FT–IR–MS), liquid chromatography–high resolution accurate mass–mass spectrometry (LC–HRAM–MS) and nuclear magnetic resonance (NMR). The steroid had an accurate mass of m/z 285.1847 (error?0.57 ppm) for the protonated species [M + H]⁺, corresponding to a molecular formula of C₁₉H₂₄O₂. Based on the GC–FT–IR–MS data, NMR data, and accurate mass, the compound was identified as androsta‐3,5‐diene‐7,17‐dione. Although this is not the first reported identification of this designer steroid in a dietary supplement, the data provided adds information for identification of this compound not previously reported. This compound was subsequently detected in another dietary supplement product, which contained three additional active ingredients.