Version 2.70

97760-3MLH1 gene methylation analysis in Blood by Molecular genetics methodActive

Term Description

MLH1 gene methylation analysis in blood is performed as an adjunct to positive hypermethylation in tumor to distinguish between somatic and germline hypermethylation, or as an adjunct to negative MLH1 germline testing in cases where colon or endometrial tumor demonstrates microsatellite instability-H (MSI-H) and loss of MLH1 protein expression.
Source: Regenstrief LOINC

Part Descriptions

LP422925-0   MLH1 gene methylation analysis
The MLH1 gene (mutL homolog 1) [HGNC Gene ID:7127] is located on chromosome 3p21.3. This gene was identified as a locus frequently mutated in hereditary nonpolyposis colon cancer (HNPCC), also known as Lynch syndrome. It is a human homolog of the E. coli DNA mismatch repair gene mutL, consistent with the characteristic alterations in microsatellite sequences (RER+phenotype) found in HNPCC. Alternative splicing results in multiple transcript variants encoding distinct isoforms. Additional transcript variants have been described, but their full-length natures have not been determined.[provided by RefSeq, Nov 2009] [NCBI Gene ID:4292] Source: National Center for Biotechnology Information (NCBI) Gene

LP422925-0   MLH1 gene methylation analysis
MLH1 gene methylation has been associated with many kinds of cancers with microsatellite instability Source: Regenstrief LOINC

LP124510-1   gene methylation
DNA methylation is essential during embryonic development, and patterns of DNA methylation are generally transmitted to daughter cells with a high fidelity. In cancer, aberrant DNA methylation patterns are found in two distinct forms: hypermethylation and hypomethylation. Hypermethylation is one of the major epigenetic modifications that repress transcription via the promoter region of tumor suppressor genes. Hypermethylation typically occurs at CpG islands in the promoter region and is associated with gene inactivation. Hypomethylation, linked to chromosomal instability and loss of imprinting, arises earlier and occurs throughout the progression of cancer.

More specifically, methylated DNA can bind to methyl-CpG-binding domain proteins (MBDs), which recruit additional proteins such as histone deacetylases and other chromatin remodeling proteins that modify histones to form compact, inactive chromatin, termed silent chromatin. Loss of methyl-CpG-binding protein 2 (MeCP2) has been implicated in Rett syndrome; and methyl-CpG-binding domain protein 2 (MBD2) mediates the transcriptional silencing of hypermethylated genes in cancer. Research has suggested that long-term memory storage in humans may be regulated by DNA methylation. Copyright Text is available under the Creative Commons Attribution/Share-Alike License. See http://creativecommons.org/licenses/by-sa/3.0/ for details. Source: Wikipedia, Wikipedia

Fully-Specified Name

MLH1 gene methylation analysis

Additional Names

Short Name
MLH1 Methyl Anl Bld
Display Name
MLH1 gene methylation analysis Molgen Doc (Bld)
Consumer Name Alpha
MLH1 gene methylation analysis, Blood

Basic Attributes

First Released
Version 2.70
Last Updated
Version 2.70
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