Basic Information

Symbol
B2M
RNA class
mRNA
Alias
Beta-2-Microglobulin Beta Chain Of MHC Class I Molecules Beta-2-Microglobin AMYLD6 MHC1D4 IMD43
Location (GRCh38)
15:44711253-44718851
UCSC Genome Browser Search in Marker Scope
Forensic tag(s)
Tissue/body fluid identification Time since deposition estimation
External database
HGNC NCBI Ensembl OMIM UniProt GTEx

MANE select

Transcript ID
NM_004048.4
Sequence length
943.0 nt
GC content
0.3913

Secondary Structure

Generated by RNAfold
Minimum free energy (MFE) structure:
Secondary structure that contributes a minimum of free energy.
Ensemble properties:
Thermodynamic properties of the Boltzmann ensemble.
Minimum free energy
-246.70 kcal/mol
Thermodynamic ensemble
Free energy: -263.86 kcal/mol
Frequency: 0.0000
Diversity: 219.68
MFE Structure Visualization
Structure Prediction
MFE Structure Prediction
...(((((((((...))).))))))...((((...((((.(((((.((((....((((((.((((.((((((((((((.(((((((.....))))).))........((((((((.......((....((((........))))..)).......)))))))).....(((((.((((.......)))))))))...(((......)))..)))).)))))))).........))))))))))..(((((.((((((....)))))).)))))(((((..((((((......(((((((..((((((......(((..(((((((.(((((((((......((((((...)))))).((((...........))))......)))))...)))).....((((((((.....(((((((..((((((.(((.((((((.....(((((((.(((((((((...........(((((((((((..(((......((((..((.((((((((((((..(((((......)))))........)))))))))))).))..))))........)))..).)))))..)))))(((((((........((((((...))))))))))))).))))))))))))))))))))))))).))))))....((((((((((.(((.(((((...................)))))..)))))))))).)))..))).)))).....)))))))).....)))))))..)))......))))))..)))))))...........))))))....))))).((((((......))))))..((((((((((((((((............)))))))....))))))))))))))))))..))))...))))(((((((((((((...))))...)))))))))...........
Thermodynamic Ensemble Prediction
...(((((((((...))).)))))).,.((((...{(((.((((,{(((({,,,((((((.((((.((((((((((((.({{((((.,...}}})).}|.|.,,...{(((((((.......({....((((........))))..}}.......)))))))),,,..|||{||(({{....,}}),,|}}}}}...{||,,....,}}..)))}.)))))))).........))))))))))..(((((.((((({....)))))).)))))(((((..((((((......(((((((..((((((......(((..(((((((.((((((((({,.{{{(,((((,..|||,,,.,,{,.,,,,}}},.}))),.,,...)))))...)))).....((((((((..,.,(((({((..{(((((.(((.((((((.....(((((((.({{((((({...........{((((((((((..(((......((((..({.((((((((((((..(((((......)))))........)))))))))))).})..))))........)))..).)))),.,))))|(((((({.......,((((((...))))))))))))),))))))))})))))))))))))))).)))))}..,.{{{{|{||||.,(({{((((....,}}}},,,..,|,|,}}}}}{||||}}}}}}}.}})..))),)))).....)))))))).....)))))))..)))......))))))..))))))).....,....,))))))....})))},,,{{{{....,,}}},.,.,|{{(((((((((((((............)))))))....))))))))))))))))))..))))...)))){|{((({{{{{{{...}||||..,})))}}}}.....,,,,,.

Transcripts

ID Sequence Length GC content
NM_004048.4 NCBI
AUUCCUGAAGCUGACAGCAUUCGGGCCGAGAUGUCUCGCUCCGUGGCCU… 943 nt 0.3913
Summary

This gene encodes a serum protein found in association with the major histocompatibility complex (MHC) class I heavy chain on the surface of nearly all nucleated cells. The protein has a predominantly beta-pleated sheet structure that can form amyloid fibrils in some pathological conditions. The encoded antimicrobial protein displays antibacterial activity in amniotic fluid. A mutation in this gene has been shown to result in hypercatabolic hypoproteinemia.[provided by RefSeq, Aug 2014] CIViC Summary for B2M Gene

Forensic Context

A study in humans demonstrated that the B2M exhibited the highest relative expression across saliva, blood, menstrual blood, and vaginal secretion stains and was among the highest in semen, showing consistent high expression across individual donors and successful detection in small and environmentally exposed stains, establishing it as an effective reference for assessing human mRNA quantity in forensic body fluid analysis [Moreno et al. DOI:10.1111/j.1556-4029.2012.02086.x]. Subsequent research in humans quantified the degradation state of the B2M transcript in dried bloodstains via ΔCq, finding its degradation rate accelerated 5-10 fold at 37°C versus 20°C and was similarly influenced by relative humidity, with ongoing investigations to incorporate these environmental effects into forensic sample age estimation [Heneghan et al. DOI:10.1016/j.fsigen.2020.102456]. A study in mice demonstrated that the B2M (B2M) is a suitable endogenous control gene for normalizing gene expression analysis after experimental traumatic brain injury, as its expression remained stable in contused brain tissue at 24 hours post-injury (+26%, not significant) and exhibited low interindividual variation (±10-40%) [Thal et al. DOI:10.1089/neu.2007.0497].