Editing Human brain (section)

===Gene and protein expression===
{{Main|Bioinformatics}}
{{See also |List of neuroscience databases}}
[[Bioinformatics]] is a field of study that includes the creation and advancement of databases, and computational and statistical techniques, that can be used in studies of the human brain, particularly in the areas of [[Bioinformatics#Gene and protein expression|gene and protein expression]]. Bioinformatics and studies in [[genomics]], and [[functional genomics]], generated the need for [[DNA annotation]], a [[Transcriptomics technologies|transcriptome technology]], identifying [[gene]]s, their locations and functions.<ref name="Steward">{{cite journal | title=Genome annotation for clinical genomic diagnostics: strengths and weaknesses | author=Steward, C.A. |display-authors=etal | pmid=28558813 | doi=10.1186/s13073-017-0441-1 | volume=9 | issue=1 | pmc=5448149 | year=2017 | journal=Genome Med | page=49 | doi-access=free }}</ref><ref>{{cite journal | title=GENCODE: the reference human genome annotation for The ENCODE Project. | author=Harrow, J. |display-authors=etal | pmid=22955987 | doi=10.1101/gr.135350.111 | pmc=3431492 | volume=22 | issue=9 | date=September 2012 | journal=Genome Res. | pages=1760–74}}</ref><ref name="Gibson and Muse">{{cite book|title=A primer of genome science|vauthors=Gibson G, Muse SV|date=April 20, 2009 |publisher=Sinauer Associates|isbn=9780878932368|edition=3rd|location=Sunderland, MA}}</ref> [[GeneCards]] is a major database.

{{as of|2017}}, just under 20,000 [[Human genome#Coding sequences (protein-coding genes)|protein-coding genes]] are seen to be expressed in the human,<ref name="Steward"/> and some 400 of these genes are brain-specific.<ref>{{Cite web|url=https://www.proteinatlas.org/humanproteome/brain|title=The human proteome in brain – The Human Protein Atlas|website=www.proteinatlas.org|access-date=September 29, 2017|url-status=live|archive-url=https://web.archive.org/web/20170929231550/https://www.proteinatlas.org/humanproteome/brain|archive-date=September 29, 2017}}</ref><ref>{{Cite journal|last1=Uhlén|first1=Mathias|last2=Fagerberg|first2=Linn|last3=Hallström|first3=Björn M.|last4=Lindskog|first4=Cecilia|last5=Oksvold|first5=Per|last6=Mardinoglu|first6=Adil|last7=Sivertsson|first7=Åsa|last8=Kampf|first8=Caroline|last9=Sjöstedt|first9=Evelina|date=January 23, 2015|title=Tissue-based map of the human proteome|journal=Science|volume=347|issue=6220|page=1260419|doi=10.1126/science.1260419|issn=0036-8075|pmid=25613900|s2cid=802377}}</ref> The data that has been provided on [[gene expression]] in the brain has fuelled further research into a number of disorders. The long term use of alcohol for example, has shown altered gene expression in the brain, and cell-type specific changes that may relate to [[alcoholism|alcohol use disorder]].<ref>{{cite journal|last=Warden|first=A|year=2017|title=Gene expression profiling in the human alcoholic brain.|journal=Neuropharmacology|volume=122|pages=161–174|pmid=28254370|doi=10.1016/j.neuropharm.2017.02.017|pmc=5479716}}</ref> These changes have been noted in the [[Synapse|synaptic]] [[transcriptome]] in the prefrontal cortex, and are seen as a factor causing the drive to alcohol dependence, and also to other [[substance abuse]]s.<ref>{{cite journal | title=Applying the new genomics to alcohol dependence. | author=Farris, S.P. |display-authors=etal | journal=Alcohol | year=2015 | pmid=25896098 | doi=10.1016/j.alcohol.2015.03.001 | volume=49 | issue=8 | pmc=4586299 | pages=825–36}}</ref>

Other related studies have also shown evidence of synaptic alterations and their loss, in the [[ageing brain]]. Changes in gene expression alter the levels of proteins in various neural pathways and this has been shown to be evident in synaptic contact dysfunction or loss. This dysfunction has been seen to affect many structures of the brain and has a marked effect on inhibitory neurons resulting in a decreased level of neurotransmission, and subsequent cognitive decline and disease.<ref name="Rozycka">{{cite journal|last1=Rozycka|first1=A|last2=Liguz-Lecznar|first2=M|title=The space where aging acts: focus on the GABAergic synapse.|journal=Aging Cell|date=August 2017|volume=16|issue=4|pages=634–643|doi=10.1111/acel.12605|pmid=28497576|pmc=5506442}}</ref><ref>{{cite journal|last1=Flores|first1=CE|last2=Méndez|first2=P|title=Shaping inhibition: activity dependent structural plasticity of GABAergic synapses.|journal=Frontiers in Cellular Neuroscience|date=2014|volume=8|page=327|doi=10.3389/fncel.2014.00327|pmid=25386117|pmc=4209871|doi-access=free}}</ref>