DNA molecular weight standard suitable for brittle X syndrome southern blot hybridization detection

Abstract

The invention discloses a DNA molecular weight standard suitable for brittle X syndrome southern blot hybridization detection. The DNA molecular weight standard contains six DNA fragments, the lengthsof the six DNA fragments are 2.8 kb, 2.9 kb, 3.3 kb, 5.2 kb, 5.3 kb and 5.7 kb respectively, and all the fragments include fragments capable of being combined with a probe for an FMR1 gene and do notcontain restriction enzyme cutting sites of EagI or EcoRI. The specific DNA molecular weight standard is provided for diagnosis of brittle X syndrome through a southern blot hybridization technology,and accurate and rapid judgment of the type of a clinical detection sample is achieved. The DNA molecular weight standard can still be normally used after being stored for 3 years at the temperatureof minus 20+ / - 5 DEG C, and the detection result is not affected. The DNA molecular weight standard is easy to prepare, has good stability and repeatability in the storage and using process and is free of biological infectivity.

Description

technical field [0001] The invention relates to the technical field of molecular biology, in particular to a DNA molecular weight standard suitable for detection of fragile X syndrome southern blot hybridization. Background technique [0002] Fragile X syndrome (FXS) is a genetic disease characterized by growth retardation and mental retardation. Recent studies have also found that FXS is also an important cause of autism spectrum disorder (ASD). [0003] The incidence of fragile X syndrome is second only to Down syndrome (trisomy 21). According to statistics, the incidence rate of males is about 1:4000, and the incidence rate of females is 1:8000-1:6000. According to conservative estimates, there are at least 200,000 Fragile X patients in my country. The main feature is moderate to severe mental retardation, and the condition tends to worsen with age. Other clinical manifestations are special facial features, such as long faces or protruding ears, which appear after pubert...

AI Technical Summary

Problems solved by technology

However, if there is no suitable DNA molecular weight standard in the hybridization analysis, it will be difficult to analyze the results

For example, female carriers may have the same degree of separation between two normal alleles of different sizes as the normal allele and the pre-mutation allele, causing the carrier to be misjudged as a normal person; Or for the judgment of the pre-mutation with a small repeat number, if there is no good DNA molecular weight standard, it will be difficult to judge the genotype according to the size of the enzyme fragment

Although the molecular typing standard can be judged internationally through the detection of multiple unknown samples, the molecular typing can be inferred; however, it lacks accuracy, and considering the difficulty of sample collection, biosafety and ethical issues, it needs to be continuously prepared and used in large quantities. It is obviously inappropriate for scientific research and clinical trials

[0006] Now there is a lack of a DNA molecular weight standard with good stability and repeatability, no biological infectivity, and reliable results that can monitor the hybridization effect and accurately type the samples.

Images