A novel method of detecting mitochondrial m.1494C>T and m.1555A>G mutations in a single PCR reaction using base-quenched probe

A novel method for detecting nine hotspot mutations of deafness genes in one tube

Deafness is a common sensory disorder. In China, approximately 70% of hereditary deafness originates from four common deafness-causing genes: GJB2, SLC26A4, GJB3, and MT-RNR1. A single-tube rapid detection method based on 2D-PCR technology was established for nine mutation sites in the aforementioned genes, and Sanger sequencing was used to verify its reliability and accuracy. The frequency of hotspot mutations in deafness genes was analysed in 116 deaf students. 2D-PCR identified 27 genotypes of nine loci according to the melting curve of the FAM, HEX, and Alexa568 fluorescence channels. Of the 116 deaf patients, 12.9% (15/116) carried SLC26A4 mutations, including c.919-2A > G and c.2168A > G (allele frequencies, 7.3% and 2.2%, respectively). The positivity rate (29.3%; 34/116) was highest for GJB2 (allele frequency, 15.9% for c.235delC, 6.0% for c.299_300delAT, and 2.6% for c.176-191del16). Sanger sequencing confirmed the consistency of results between the detection methods based on 2D-PCR and DNA sequencing. Common pathogenic mutations in patients with non-syndromic deafness in Changzhou were concentrated in GJB2 (c.235delC, c.299_300delAT, and c.176-191del16) and SLC26A4 (c.919-2A > G and c.2168 A > G). 2D-PCR is an effective method for accurately and rapidly identifying deafness-related genotypes using a single-tube reaction, and is superior to DNA sequencing, which has a high cost and long cycle.

The mechanism and regularity of quenching the effect of bases on fluorophores: the base-quenched probe method

The base-quenched probe method for detecting single nucleotide polymorphisms (SNPs) relies on real-time PCR and melting-curve analysis, which might require only one pair of primers and one probe.

Detection of simultaneous multi-mutations using base-quenched probe

The base-quenched probe method for detecting single nucleotide polymorphisms (SNPs) relies on real-time PCR and melting-curve approaches. Here, we applied the most common commercial fluorophores including FAM, HEX, CY5, CY3, TET, JOE, Texas Red and ROX for labeling probes to detect multi-mutations simultaneously according to the different fluorescence channels. Accuracy of the method was confirmed by direct sequencing. The results demonstrated that all above dyes could be influenced by bases and could be applied to detect SNPs. Furthermore, this method was applied to detect APOM rs707921, APOM rs707922 and MCP-1 rs1024611 simultaneously, which was demonstrated successfully.

Association between the ABCC11 gene polymorphism and the expression of apolipoprotein D by the apocrine glands in axillary osmidrosis

It has been suggested that the adenosine triphosphate‑binding cassette sub‑family C member 11 (ABCC11) gene polymorphism and apolipoprotein D (ApoD), an odor precursor carrier, may be important in the formation of axillary odor. To date, few studies have examined the potential correlation between these two factors. The present study aimed to investigate the association between a 538 G>A single‑nucleotide polymorphism (SNP) of the ABCC11 gene and the mRNA expression levels of ApoD in the apocrine gland of patients with osmidrosis. The 538 G>A polymorphism genotypes of 33 patients with a clinical diagnosis of osmidrosis were analyzed by polymerase chain reaction (PCR) and a base‑quenched probe method, and they were divided into two groups according to the results. The G allele functions as a dominant gene; therefore, patients with the GG or GA genotype were allocated to Group I (n=28) and patients with the AA genotype to Group II (n=5). The mRNA expression levels of ApoD in the apocrine glands were determined by reverse transcription‑PCR. The results indicated that the mRNA expression levels of ApoD were significantly higher in the apocrine glands of patients in Group I compared with those in Group II (P<0.01). In conclusion, the results indicated that the ABCC11 gene SNP of the 538 G>A allele was associated with a downregulation of the mRNA expression of ApoD in the apocrine glands, which may indicate a role for the ABCC11 gene in the mediation of osmidrosis by enhancing the transition of odor precursors via the ApoD pathway.