Ion-Regulated Signal Amplification Optical Microfiber Interferometric DNA Sensor.

Genetic information sensors play a pivotal role in the biomedical field. The detection of deoxyribonucleic acid (DNA) is achieved experimentally using an optical microfiber interferometric sensor, which operates based on an ion-regulation sensitivity enhancement mechanism. The optical microfiber is fabricated by drawing optical fiber into a diameter of less than 10 μm via the melting and tapering technique.

[Hemoglobin H disease with a rare α-thalassemia gene mutation (--/αα): pedigree analysis and genetic diagnosis].

Objective: To identify a rare α-thalassemia gene mutation in a family from south China and perform a pedigree analysis and genetic diagnosis of hemoglobin H (HbH) disease caused by this mutation.

Methods: Peripheral blood samples were collected from the family members for analysis of the hematological phenotype and routine test of thalassemia genes. DNA sequencing was carried out for samples that showed genotype and phenotype inconsistency.

Rapid detection of Down's syndrome using quantitative real-time PCR (qPCR) targeting segmental duplications on chromosomes 21 and 11.

Objective: Development of a qPCR test for the detection of trisomy 21 using segmental duplications.

Methods: Segmental duplications in the TTC3 gene on chromosome 21 and the KDM2A gene on chromosome 11 were selected as molecular markers for the diagnostic qPCR assay. A set of consensus primers selected from the conserved regions of these segmental duplications were used to amplify internal diverse sequences that were detected and quantified with different probes labeled with distinct fluorescence.

Rapid diagnosis of aneuploidy using segmental duplication quantitative fluorescent PCR.

The aim of this study was use a simple and rapid procedure, called segmental duplication quantitative fluorescent polymerase chain reaction (SD-QF-PCR), for the prenatal diagnosis of fetal chromosomal aneuploidies. This method is based on the co-amplification of segmental duplications located on two different chromosomes using a single pair of fluorescent primers. The PCR products of different sizes were subsequently analyzed through capillary electrophoresis, and the aneuploidies were determined based on the relative dosage between the two chromosomes.

Detection of three common α-thalassemia in non-deletion types and six common thalassemia in deletion types by QF-PCR.

Objective: Thalassemia is one of the most common monogenic hereditary diseases in tropical and subtropical regions. An effective way to avoid the birth of severe thalassemia patients is to strengthen the thalassemia screening of couples before wives are pregnant. Thalassemia gene carriers can be diagnosed by molecular biology in order to conduct effective guidance for fertility.

Rapid diagnosis of aneuploidy in chromosomes 13, 18, 21, X and Y by quantitative fluorescence-PCR combined with short tandem repeat and fluorescence-labeled homologous gene quantitative‑PCR using 4-color fluorescently labeled universal primers.

The present study aimed to develop a rapid diagnostic test of aneuploidy in chromosomes 13, 18, 21, X and Y through a program combining short tandem repeat (STR) typing with fluorescence-labeled homologous gene quantitative‑polymerase chain reaction (fHGQ-PCR), which avoids misjudgment risks by using one method alone. Furthermore, fluorescently labeled universal primers not only ensure the accuracy of the results but also reduces the cost of fluorescent labels. The verification of DNA extracted from samples confirmed by karyotype analysis with quantitative fluorescence (QF)-PCR shows that the results obtained using the QF-PCR program are consistent with the results of karyotype analysis in rapidly diagnosing the aneuploidy of chromosomes 13, 18, 21, X and Y.

[Construction and identification of the chromosome specific DNA library.].

The objective of the present study was to construct a human chromosome 21 specific DNA library for further use in research of genetic disease. Human chromosome 21 microdissected from the peripheral blood cells were subjected to repeatedly incubation in gradient temperature bath to release DNA. The library of chromosome 21 was constructed using the DNA fragment of 100-500 bp and 500-2 000 bp recovered from the products of DOP-PCR.