Identification of a novel mutation in solute carrier family 29, member 3 in a Chinese patient with H syndrome.

BACKGROUND: H syndrome (OMIM 612391) is a recently described autosomal recessive genodermatosis characterized by indurated hyperpigmented and hypertrichotic skin, as well as other systemic manifestations. Most of the cases occurred in the Middle East areas or nearby countries such as Spain or India. The syndrome is caused by mutations in solute carrier family 29, member 3 (SLC29A3), the gene encoding equilibrative nucleoside transporter 3. The aim of this study was to identify pathogenic SLC29A3 mutations in a Chinese patient clinically diagnosed with H syndrome. METHODS: Peripheral blood samples were collected from the patient and his parents. Genomic DNA was isolated by the standard method. All six SLC29A3 exons and their flanking intronic sequences were polymerase chain reaction (PCR)-amplified and the PCR products were subjected to direct sequencing. RESULTS: The patient, an 18-year-old man born to a nonconsanguineous Chinese couple, had more extensive cutaneous lesions, involving both buttocks and knee. In his genomic DNA, we identified a novel homozygous insertion-deletion, c. 1269_1270delinsA, in SLC29A3. Both of his parents were carriers of the mutation. CONCLUSIONS: We have identified a pathogenic mutation in a Chinese patient with H syndrome.

Quick genetic screening using targeted next-generation sequencing in patients with tuberous sclerosis.

Tuberous sclerosis complex is an autosomal dominant disorder characterized by hamartomas in multiple organ systems. Mutations in the 2 large genes TSC1 and TSC2 have been demonstrated to be associated with tuberous sclerosis complex by various mutation screening methods. Targeted next-generation sequencing for genetic analysis is performed in the current study and is proved to be less cost, labor, and time consuming compared with Sanger sequencing. Two de novo and 1 recurrent TSC2 mutation in patients with tuberous sclerosis complex were revealed. Clinical details of patients were described and the underlying mechanism of the 2 novel TSC2 mutations, c.245G>A(p.W82X) and c.5405_5408dupACTT(p.P1803Lfs*25), were discussed. These results added to variability of TSC mutation spectrum and suggest that targeted next-generation sequencing could be the primary choice over Sanger sequencing in future tuberous sclerosis complex genetic counseling.