遗传学实验技术

Nucleic acid probes are an important tool in molecular diagnosis. To facilitate the detection of hybridized probes, they are labeled with a reporter molecule, which is usually a radioisotope. For diagnostic techniques carried out in a clinical laboratory, radioisotopes are hazardous ...

Conventional polymerase chain reaction (PCR) enables reliable amplification of 3–4 kb of DNA (1) while attempts at optimisation has enabled 15.6 kb of λ DNA to be amplified (2). The maximum amplifiable length of PCR is limited by the low fidelity of the Thermus aquaticus (Taq) DNA polymerase (3), the mo ...

Restriction analysis of polymerase chain reaction (PCR) products is one of the earliest techniques used for analyzing amplification products (1). This approach is applicable for distinguishing alleles in which the polymorphic residue results in the creation or removal of a restric ...

Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis is a simple and sensitive method to detect DNA alterations including even one point mutation. A disadvantage of PCR-SSCP, despite its sensitivity, is the necessity to use radioisotopes. To avo ...

Microsatellites (or simple sequence length polymorphisms ; and short tandem repeat polymorphisms ) are tandemly repeated arrays of short stretches of nucleotide sequences, typically (dA-dC/dT-dG), where n is between 15 and 30 (1,2) The human genome is estimated to contain approximate ...

Human tuberculosis (TB) resulting from Mycobacterium tuberculosis and occasionally Mycobacterium bovis infection had been in decline for many decades, in the western world, owing to the advent of effective anti-microbial therapies and good public health programs that have contr ...

The hepatitis C virus (HCV) is an orgainsm of the age of molecular biology, for its discovery and much of the research into the infection have relied heavily on molecular techniques. The development of molecular cloning enabled a successful strategy that finally identified HCV (1)as the cause of 9 ...

The polymerase chain reaction (PCR) is an in vitro method for the amplification of DNA that was introduced in 1985 (1). The principle of the PCR is elegantly simple but the resulting method is extremely powerful. The adoption of the thermostable Taq polymerase in 1988 greatly simplifies the process ...

The incidence of chromosomal abnormalities in liveborn infants has been established to be about 1 in 170 newborns (1). The most frequent chromosomal anomalies are aneuploidies involving chromosomes 21,18,13, and both sex chromosomes. Prenatal diagnosis of chromosomal disorders is ...

Prenatal diagnosis of hereditary diseases is usually performed by collecting fetal samples using amniocentesis, chorionic villus sampling (CVS), or cordocentesis. However, these procedures are associated with some degree of risk. For example, abortion owing to hemorrhage or in ...

It is a long-term goal of human genetics to develop prenatal diagnostic tests that are noninvasive and which do not constitute a risk to the mother or fetus. Such tests would be highly desirable compared with current techniques that require the sampling of fetal tissues by invasive measures such as a ...

The analysis of genetic material is fundamental to many medical and scientific applications. These include diagnosis of genetic disorders from preimplantation embryos (1) prenatal diagnosis (amniocentesis and chorionic villus sampling ), forensic analysis (2) analysis of pa ...

Many studies have shown that survival following surgery for solid tumors, such as colorectal and breast, is influenced by the extent of local invasion and the presence of distant metastases, and staging systems based on that are still the main prognostic indicator of survival. However, 20–30% of ...

The ability of the polymerase chain reaction (PCR) to amplify from partially degraded and relatively impure preparations has allowed the technique to amplify nucleic acid sequences from archival materials, which in many institutions consist of paraffin-embedded tissue samples ...

Despite advances in cancer treatment, disseminating disease continues to pose a major problem in clinical management. The dissemination of cancer cells around the body, or metastasis, involves multiple tumor-host interactions. The relatronship between circulating tumor cel ...

The CD44 molecule is a transmembrane glycoprotein, it is an acidic, sul fated protein that contains multiple phosphoserine residues and several intrachain disulfide bonds. It is essentially composed of a 37-kDa protein core highly glycosylated by N- and O-linked sugars to form an 85–90-kDa p ...

A large number of mitochondrial disorders have been associated with mutations in mitochondrial DNA (mtDNA) (1–5). Disorders of mtDNA can be divided into three groups: large rearrangements of the mitochondrial genome, point mutations in transfer RNA (tRNA) or coding genes, and a reduction in ...

Allogeneic bone marrow transplantation (BMT) has become a recognized therapy for the treatment of patients with leukemia, severe combined immune deficiency (SCID) and severe aplastic anemia (SAA). It was originally assumed that complete donor chimerism was essential for sustain ...

Reverse transcriptase polymerase chain reaction (RT-PCR) has become a well-established and powerful molecular technique for studying ribonucleic acids. It is used in medical diagnostics for detecting viral RNA, in hematology and oncology for detecting chimeric transcripts of ...

It is often necessary to obtain DNA sequence information following successful amplification. Although polymerase chain reaction (PCR) products may be cloned into a vector and sequenced at a later stage, it is often preferable to sequence PCR products directly, without subcloning, and it ...