Genevieve Houston-Ludlam
Genetics BSCI 222H, Fall 2002
University of Maryland
  Printed with the permission of the author

Trisomy-21, known more commonly as Down syndrome (DS), is the most common genetic cause of mental retardation in the human population, affecting approximately 1 out of every 704-780 pregnancies (1). In addition to mental retardation (2) and impairments in motor skills (3) and speech (4), numerous degenerative health problems are associated with DS, such as frequent illness due to a suppressed immune system (5) increased frequency of autoimmune disorders (6), accelerated aging (7), increased incidence of leukemia (8), increased incidence of endocrine dysfunction (9), neuronal death (10), reduction in neurotransmitters (11) and increased frequency and earlier onset of Alzheimer disease (12).

There are two basic opinions about the situation of people with DS. The current mainstream opinion is that DS is a genetic disorder, and therefore cannot be fundamentally changed. The emerging alternative view is that this disease is the result of multiple interacting gene overexpressions, essentially multiple inborn errors of metabolism, and if we can discover ways to normalize gene function by either controlling the conditions for gene expression, or rebalancing the resulting biochemical dysregulation, that we can mitigate some of the resulting disease. For example, the gene SOD1, located on chromosome 21, is overexpressed, and the resulting oxidative stress can account for much of the neuronal loss and premature aging seen in DS. (13,14) Consequently, antioxidant therapy through diet and supplementation, may be extremely helpful in improving the health and intellectual potential of people with DS(15). Other nutritional interventions including zinc and factors supporting the interrelated folic acid and SAMe cycles also show potential for benefit.(16)

Human Chromosome 21 was first mapped in May, 2000. (17) Much is known about many of the genes that are on chromosome 21, and that knowledge is scattered throughout a variety of online databases and the medical literature in the form of individual articles. The OMIM genome database (18) contains the name and location of the genes, and links for various references into Medline (19). Information about enzymes is contained in the ExPASy (20) database. The gene names do not always match the enzyme names in ExPASy due to the differences in naming conventions used by different scientific disciplines.

I have taken each gene on Chromosome 21, as listed in the original article from Nature publishing the complete sequence of the chromosome, and included the following information:
  1. The gene name as listed in the original article sequencing chromosome 21,
  2. The gene location, with a link into OMIM (recognized genes) and if no OMIM record existed, a link into Nucleotide (mostly pseudogenes and predicted genes)
  3. The EC number with a link into the appropriate record in the EXPASY database if the gene in question is an enzyme (or predicted to be) and is identified to the specific enzyme,
  4. The full name of the gene as listed in the original article (with changes if newer information was in OMIM),
  5. Category of this gene as follows:
    1. E for an enzyme,
    2. S for a structural protein (eg. A subunit of collagen),
    3. F for a functional protein (eg. Something that supports cellular processes such as a receptor or drug resistance),
    4. T for a gene related to transcription, translation, replication or gene regulation,
    5. P for a pseudogene, and
    6. U for unknown in the original publication and I could find no further elucidation in the research.
  6. Genes were categorized into a particular category even if it was a subunit of that particular type of protein, or if the gene was a putative gene in that category. Consequently, the number of genes in a functional category (enzyme, structural, functional or transcription related) may not represent fully functional proteins.
  7. For enzymes, evidence of overexpression of this particular gene, and a link into Medline with the evidence. Categories are Y if there is evidence that it is overexpressed, N if there is evidence that it is not overexpressed, or NE for no evidence one way or the other. For gene PDE9A, there was an enzyme that was similar to the enzyme name, but not exact, that was identified as overexpressed, so it was categorized as NE, with a link to the paper in question. No attempt was made to look for enzymes that had only been categorized to family and not specific enzyme.
When completing this project, there were some discrepancies in the databases that I was not able to resolve. PRED41, UMODL1 and KAPcluster were not located in either the Nucleotide or the OMIM databases. KIAA0635 was only listed in Homo sapiens for chromosome 4, with no listing in for chromosome 21. Further, there were several genes listed in OMIM as belonging to chromosome 21 that could not be reconciled with the list in the sequence as follows: TAM, USH1E, CRFB4, GANP/MAP80, ITGB2, KNO, SFRS2IP, TMEM1, AABT.

For the enzymes, there were a number of enzymes that were identified to the enzyme family, but not specific enzymes. There were no appropriate pages in ExPASy to link to, so links were not included for those enzymes.

In a sense, this project is a catalog of what we already know about this chromosome, particularly as it relates to DS. It is hoped that by gathering together what we already know about this chromosome, it will assist in generating hypotheses regarding connections between specific genes and the disease processes seen so frequently in DS, with the hope of discovering ways to mitigate these disease processes.

GeneLocationEnzymeEnzyme NameCategoryOver-
TPTE21p11EC; putative protein-tyrosine phosphatase, EC
CYC1LP421p11 Cytochrome c pseudogeneP 
Pseudo121p11 Zinc Finger Protein pseudogeneP 
PRED121p11EC2.7.1putative gene, protein kinase E ETA type (EC 2.7.1.) likeE 
ORLP121p11.2 Pheromone receptor pseudogeneP 
Pseudo1.121p11 pseudogene similar to cDNA DKFZp586E1423P 
Pseudo221p11 tubulin tyrosine ligase-like 1 pseudogeneP 
EIF3S5P21p11 eukaryotic initiation factor-3, subunit 5 pseudogeneP 
PRED6521q11.1 putative gene with similarity to zinc finger proteinsT 
PRED321q11.1 putative gene, proto-oncogene protein precursor likeT 
PRED421q11.1 putative gene with similarities to KIAA1074 and KIAA0565U 
ORLP221q11.1 Pheromone receptor pseudogeneP 
CNN221q11.1 calponin 2S 
C21orf1521q11 spliced EST AJ003450U 
CYP4F3LP21q11 Cytochrome P450 pseudogeneP 
NF1L1P21q11.1 neurofibromatosis type 1 pseudogeneP 
PRED521q11.2 putative gene, lipase EC likeE 
RBM1121q11.2 putative gene, RNA binding motif protein 11 likeT 
PRED621q11.2 putative gene, multidrug resistance associated protein likeF 
STCH21q11.1 human microsomal stress 70 protein ATPase coreF 
SAMSN-121q11.2 gene with homology to KIAA0790 proteinU 
POLR2CP21q11.2 pseudogene similar to RNA polymerase H subunitsP 
NRIP121q11.1 nuclear factor RIP140T 
CYC1LP521q11.2 Cytochrome c pseudogeneP 
RAD23BLP21q11.2 UV excision repair protein pseudogeneP 
USP2521q11.2 ubiquitin specific protease USP25E 
RBPMSLP21q11.2 RNA-binding protein hermes pseudogeneP 
C21orf3421q21.1 spliced EST AA451643U 
VDAC2P21q21.1 voltage-dependent anion channel isoform 2 pseudogeneP 
C21orf3521q21.1 spliced EST AW242517U 
C21orf3621q21.1 spliced EST AA017197U 
C21orf3721q21.1 spliced EST N47348U 
CXADR21q21.1 46 kD coxsackievirus and adenovirus receptor (CAR) proteinF 
BTG321q21.1 B-cell translocation geneU 
YG8121q21.1 gene of unknown function, spliced variant EST AI126619U 
C21orf3921q21.1 spliced EST T74237U 
RL37P21q21.1 human ribosomal protein L37 pseudogeneP 
PRED1221q21.1 putative gene, membrane protein likeS 
PRSS721q21.1EC enterokinaseENE
SLC6A6P21q21.1 taurine transporter processed pseudogeneP 
RL37P221q21.1 human ribosomal protein L37 pseudogeneP 
C1QBPP21q21.1 human splicing factor 2 hyaluronic acid-binding protein (SF2p32) pseudogeneP 
C21orf4021q21.1 spliced EST AA412132U 
FDPSP21q21.1 faresyl pyrophosphate synthetase processed pseudogeneP 
KRT18P221q21.1 cytokeratin 18 processed pseudogeneP 
RPS3AP21q21.1 ribosomal protein S3 processed pseudogeneP 
PRED1421q21.1 human cDNA clone 280692U 
PPIAP21q21.1 cyclophilin-related processed pseudogeneP 
NCAM221q21 neural cell adhesion molecule 2 precursorF 
PRED1521q21.2 exon prediction onlyU 
PRED1621q21.2 spiced EST AI188136U 
Pseudo321q21.2 ETS-like processed pseudogeneP 
Pseudo421q21.2 ERK3 protein kinase pseudogeneP 
ZNF299P21q21.2 zinc finger-like processed pseudogeneP 
EEF1A1P21q21.2 human elongation factor EF-1-alpha processed pseudogeneP 
TUBAP21q21.2 alpha tubulin (TUBA2) processed pseudogeneP 
C21orf5321q21.2 spliced EST W73844U 
RPL13AP21q21.2 ribosomal protein RPL 13A pseudogeneP 
C21orf4221q21.2 spliced EST AA442272U 
PRED2121q21.2 spliced EST AI016585U 
MRPL3921q21.3 Mitochondrial Ribosomal Protein L39 (MRPL39)T 
PRED2221q21.2 complete cDNA FLJ20451U 
JAM221q21.2 junctional adhesion moleculeS 
FDXP221q21.2 adrenodoxin pseudogeneP 
ATP5A21q21.2 human mitochondrial ATPase coupling factor 6 subunitE 
GABPA21q21.2 human nuclear respiratory factor-2 subunit alphaT 
APP21q21.2 human mRNA for amyloid A4 precursor of Alzheimer's diseaseS 
PRED2421q21.2 gene similar to MARCKS, cDNA DKFZp564P1664U 
ADAMTS121q21.2 human metallopoteinase with thrombospondin type 1 motifsE 
ADAMTS521q21.2 disintegrin-like and metalloprotease with thrombospondin type 1 motif, 5E 
GPXP221q21.2 human glutathione peroxidase (GPXP2) pseudogeneP 
PRED2521q21.2 exon prediction onlyU 
EIF4A1P21q21.2 eukaryotic initiation factor 4AI pseudogeneP 
RPL10P21q21.2 60S ribosomal protein L 10 pseudogeneP 
PRED2621q21.2 exon prediction onlyU 
D21S207321q21.2 KIAA0253 pseudogeneP 
C21orf2321q21.2 spliced EST AI796012U 
PRED2721q22.1 exon prediction onlyU 
N6AMT121q21.2 putative N6-DNA-methyltransferaseE 
HSPDP721q21.3 human chaperonin pseudogeneP 
ZNF29421q22.1 zinc finger proteinT 
RPL23P221q22.11 60S ribosomal protein L 23 pseudogeneP 
C21orf621q22.11 chromosome 21 open reading frame 6U 
USP1621q22.11EC ubiquitin processing protease EC
CCT821q22.11 T-complex protein 1, theta subunitS 
C21orf721q22.3 putative gene, TGF-beta activated kinase likeE 
GAPDP1421q22.1 glycerinaldehyde-3-phosphate dehydrogenase pseudogeneP 
BACH121q22.1 transcription regulator proteinT 
C21orf1221q22.1 spliced EST R82144 (trapped exon)U 
C21orf821q22.1 spliced EST AA843704U 
GRIK121q22 human glutamate receptor (GLUR5)F 
C21orf4121q22.11 spliced EST N45393U 
C21orf921q22.1 spliced EST W58369, nuclear factorT 
CLDN1721q22.11 human CLDN17 gene for claudin-17S 
CLDN821q22.1 human CLDN8 gene for claudin-8S 
PRED2921q22.1 exon prediction onlyU 
PRED3021q22.1 exon prediction onlyU 
UBE3AP221q22.1 ubiquitin protein ligase, processed pseudogeneP 
TIAM121q22.1 human T-lymphoma invasion and metastasis inducing TIAM1 proteinT 
PRED3121q22.1 exon prediction onlyU 
BTRC2P21q22.1 pseudogene similar to BTRCP 
SOD121q22.1EC Superoxide DismutaseEY
CTBP221q21.3 C-terminal binding protein 2F 
HMG14P21q22.11 nonhistone chromosomal protein HMG-14 pseudogeneP 
HUNK21q22 Hormonally upregulated NEU-associated kinaseE 
C21orf4421q22.1 spliced EST AW138869U 
C21orf4521q22.11 spliced EST AI369385U 
KIAA053921q22.1 human mRNA for KIAAA0539 protein- open reading frame 108U 
PRED3421q22.1 putative gene, similar to C. elegans P91865, spliced EST H51862- open reading frame 63U 
C21orf4721q21.1 spliced EST H51284U 
TCP10L21q21.1 gene similar to TCP10, spliced ESTs AA465232/T18865U 
SYNJ121q22.2 synaptojanin-1, polyphosphoinositide phosphataseE 
GCFC21q22.1 human GC-rich sequence DNA-binding factor candidate- open reading frame 66T 
C21orf4921q22.1 spliced EST T19019U 
PRED3621q22.1 exon prediction onlyU 
PRKCBP221q22.1 human protein kinase C-binding protein RACK17F 
C21orf5421q22.1 spliced EST AA934973U 
IFNAR221q22.1 human interferon alpha/beta receptorF 
IL10RB21q22.1 human transmembrane receptor protein; cytokine receptorF 
IFNAR121q22.1 human interferon alpha receptor (HiIFN-alphapRec)F 
IFNGR221q22.1 interferon-gamma receptor beta chain precursorF 
C21orf421q22.1 chromosome 21 open reading frame 4 (interferon receptor cluster)F 
RPS5L21q22.1 human ribosomal protein S5 mRNA, complete cdsT 
C21orf5521q22.11 spliced ESTs AA233864/AA232809U 
GART21q22.1EC formyltransferaseEY
C21orf5021q22.1 spliced EST AA658915U 
SON21q22.1 SON DNA-binding protein, KIAA1019T 
CRYZL121q21.1 human quinone oxidoreductase homolog-1E 
ITSN121q22.1 Intersectin 1 (SH3 domain protein-1A)F 
ATP5021q22.1 human ATP synthase OSCP subunit, oligomycin sensitivity conferring proteinE 
SLC5A321q22 human solute carrier family 5, member 3, sodium/myo-inositol cotransporterF 
PRED3721q22.1 exon prediction onlyU 
KCNE221q22.1 human minK-related peptide 1, potassium channel subunit, MiRP1F 
C21orf5121q22.1 spliced EST AA306264U 
PRED3821q22.1 exon prediction onlyU 
KCNE121q22.1 Potassium voltage-gated channel, Isk-related subfamily, member 1 (cardiac)F 
DSCR121q22.1 Myocyte-enriched calcineurin-interacting protein 1U 
PRED3921q22.1 exon prediction onlyU 
CLIC1L21q22.1 putative gene, p64 chloride channel like, spliced ESTs T92523/T91760F 
C21orf5221q22.1 spliced EST AI761253U 
RUNX121q22.3 acute myeloid leukemia 1 protein (oncogene AML-1), core binding factor, alpha subunitT 
RPL34P321q22.1 pseudogene with similarity to ribosomal protein L34P 
RPS20P21q22.1 pseudogene with similarity to ribosomal protein S20P 
PPP1R2P221q22.1 protein phosphatase inhibitor 2 pseudogeneP 
PRED4021q22.1 exon prediction onlyU 
RPL23AP321q22.1 ribosomal protein L23A pseudogeneP 
C21orf1821q22.1 spliced EST AK001660U 
RIMKLP21q22.1 pseudogene for KIAA1238 protein, similar to bacterial ribosomal S6 modification proteinP 
C21orf2721q22.1 spliced EST AI685287U 
CBR121q22.1EC reductase (NADPH) 1, EC1.1.1.184EY
C21orf1921q22.1 unspliced ORFU 
RPS9P21q22.1 ribosomal protein S9 pseudogeneP 
CBR321q22.2 carbonyl reductase (NADPH) 3, EC1.1.1.184E 
C21orf521q22.2 chromosome 21 open reading frame 5U 
RPL3P21q22.1 ribosomal protein L3 pseudogeneP 
SFRS9P121q22.1 splicing factor pseudogeneP 
RPS26P21q22.1 ribosomal protein S26 pseudogeneP 
KIAA013621q22.1 human mRNA for KIAA0136 proteinU 
CHAF1B21q22.2 human chromatin assembly factor -I p60 subunitT 
ATP5J2LP21q22.1 F1Fo-ATPase synthase f subunit pseudogeneP 
CLDN1421q22.3 human CLDN14 gene (autosomal recessive deafness)U 
PSMD4P21q22.1 proteasome 26S subunit pseudogeneP 
PRED41n/a exon prediction onlyU 
SIM221q22.2 human transcription factor SIM2, homolog of the Drosophila single-minded gene SIM1T 
HLCS21q21.1EC 6.3.4holocarboxylase synthetase, EC6.3.4E 
DSCR521q22.1 human Down syndrome critical region protein CU 
TTC321q22.2 tetratricopeptide repeat protein 3 (TPR repeat protein D)U 
DSCR321q22.3 Down syndrome critical region protein AU 
DYRK1A21q22.1EC 2.7.1dual-specificity tyrosine-Y-phosphorylation regulated kinase, EC 2.7.1E 
KCNJ621q22.1 human G protein coupled inward rectifier potassium channel 2 (hiGIRK2)F 
DSCR421q22.2 Down syndrome critical region protein BU 
KCNJ1521q22.2 inwardly rectifying potassium channel Kir4.2F 
ERG21q22.3 transcriptional regulator ERG (transforming protein ERG)T 
C21orf2421q22.2 spliced EST AI492145U 
ETS221q22.3 human erythroblastosis virus oncogene homolog 2T 
RPL23AP521q22.2 60S ribosomal protein pseudogeneP 
PCBP2P121q22.3 heteronucleotide robosomal protein pseudogeneP 
DSCR221q22.3 leucine rich protein C21-LRPU 
N14321q22.3 human mRNA; transcriptional unit N143T 
WDR921q22.3 gene homolog to cAMP response element binding and beta-tranducin familyF 
HMG1421q22.3 human non-histone chromosomal protein HMG-14T 
WRB21q22.3 tryptophan-rich protein, congenital heart disease 5 proteinS 
C21orf1321q22.3 hypothetical 76.5 kD protein, O95447, myosin heavy chain and kinesin homologyT 
SH3GBR21q22.3 21-glutamic acid-rich Protein (21-GARP)U 
B3GALT521q22.3 GlcNAc-beta-1,3 galactosyltransferase 5E 
IGSF521q22.3 putative gene, immunoglobulin superfamily 5 likeF 
PCP421q22.3 brain-specific polypeptide PEP19S 
DSCAM21q22.2 human CHD2-52 down syndrome cell adhesion moleculeS 
PRED4221q22.3 exon prediction onlyU 
BACE221q22.3EC 3.4.23beta-site APP cleaving enzyme 2, EC3.4.23E 
PRED4321q22.3 exon prediction onlyU 
PRED4421q22.3 putative gene containing transmembrane domainS 
C21orf1121q22.3 gene similar to 2-19 proteinU 
MX221q22.3 human interferon-regulated resistance GTP-binding protein MXBF 
MX121q22.3 human interferon-regulated resistance GTP-binding protein MXAF 
TMPRSS221q22.3EC 3.4.21transmembrane protease, serine 2 EC 3.4.21E 
C21orf2021q22.3 spliced EST AW128631U 
C21orf2121q22.3 spliced EST AA969880U 
C21orf2221q22.3 spliced EST AA4359939U 
ANKRD321q22.3 Ankyrin repeat domain 3- protein kinaseE 
ZNF29821q22.3 putative gene containing C2 domain, spliced EST AA490433U 
C21orf2521q22.3 human cDNA DKFZp586F0422 AL050173U 
ZNF29521q22.3 gene similar to zinc finger 5 proteinT 
UMODL1n/a gene similar to uromodulinF 
PRED4621q22.3 exon prediction onlyU 
ABCG121q22.3 white protein homolog (ATP-binding cassette transporter 8)F 
TFF321q22.3 trefoil factor 3, HITF, human intestinal trefoil factorS 
TFF221q22.3 trefoil factor 2, SML1, human spasmolytic polypeptideS 
TFF121q22.3 trefoil factor 1, BCE1, human pS2 induced by estrogen from human breast cancer cell line MS 
TMPRSS321q22.3 gene similar to transmembrane serine proteaseE 
UBASH3A21q22.3 gene similar to UBA containing SH3 domainF 
TSGA221q22.3 human homolog to mouse testis specific gene 2F 
SLC37A121q22.3 gene similar to glycerol-3-phosphate permeaseE 
PDE9A21q22.3EC 3',5'-cyclic phosphodiesterase type 9, EC
WDR421q22.3 WD repeat domain 4U 
NDUFV321q22.3 NADH-ubiquinone oxidoreductase 9 kD subunit precursor, EC 
PKNOX121q22.3 human homeobox-containing proteinU 
CBS21q22.3EC cystathionine-beta-synthase, EC
U2AF121q22.3 human U2 snRNP auxiliary factor small subunitF 
CRYAA21q22.3 human alphaA-crystallin (CRYA1)S 
HSF2BP21q22.3 heat shock transcription factor 2 binding proteinF 
PRED4721q22.3 exon prediction onlyU 
PRED4821q22.3 exon prediction onlyU 
SNF1LK21q22.3 gene similar to rat protein kinase (KID2)E 
PRED4921q22.3 exon prediction onlyU 
PRED5021q22.3 exon prediction onlyU 
PRED5121q22.3 exon prediction onlyU 
RPL31P21q22.3 ribosomal protein L31 pseudogeneP 
H2BFS21q22.3 H2B histone family S memberT 
KIAA017921q22.3 human mRNA for KIAA0199 proteinU 
PDXK21q22.3EC pyridoxal kinase, EC
CSTB21q22.3 cystatin B (liver thiol proteinase inhibitor)F 
D21S2056E21q22.3 human NNP-1/Nop52 (NNP-1) novel nuclear protein 1T 
PRED5221q22.3 exon prediction onlyU 
MYL6P21q22.3 myosine alkali light chain 6 pseudogeneP 
AGPAT321q22.3 gene similar to plant lysophosphatidic acid acyltransferaseE 
HPE121q22.3 Holoprosencephaly-1, alobarS 
H2AFZP21q22.3 histone H2AZ pseudogeneP 
PWP2H21q22.3 periodic tryptophan protein 2 homologF 
ES121q22.3 human HES1 protein, homolog to E. coli and zebrafish ES1 proteinU 
C21orf3221q22.3 putative gene with similarities to yeast gene YDL038cU 
KIAA0635n/a human mRNA for KIAA0635 proteinU 
DNMT3L21q22.3 human cytosine-5-methyltransferase 3-like proteinE 
AIRE21q22.3 autoimmune regulator (APECED protein)F 
PFKL21q22.3EC liver-type 1-phosphofructokinase, EC2.7.1.11EY
C21orf221q22.3 nuclear encoded mitochondrial protein, cDNA A2-YF5F 
TRPC721q22.3 transient receptor potential-related channel 7, a novel putative Ca2+ channel proteinF 
C21orf3021q22.3 intronless long ORF, AL117578U 
C21orf2921q22.3 spliced partial mRNAU 
C21orf3121q22.3 spliced EST AJ003549/AJ003550/AJ003554U 
PRED5321q22.3 exon prediction onlyU 
KAPclustern/a keratin associated proteins, gene clusterS 
IMMTP21q22.3 motorprotein pseudogeneP 
UBE2G221q22.3 human ubiquitin conjugating enzyme G2E 
SMT3H121q22.3 ubiquitin-like protein, a human homolog of the S. cerevisiae SMT3 geneT 
PTTG1IP21q22.3 Pituitary tumor-transforming gene 1 protein-interacting proteinF 
ITGB221q22.3 cell curface adhesion glycoprotein (LFA-1/CR3/P150,959 beta subunit precursor)S 
PRED5421q22.3 exon prediction onlyU 
PRED5521q22.3 exon prediction onlyU 
PRED5621q22.3 exon prediction onlyU 
ADARB121q22.3EC 3.5human dsRNA adenosine deaminase DRADA2b, EC 3.5E 
PRED5721q22.3 exon prediction onlyU 
PRED5821q22.3 exon prediction onlyU 
KIAA095821q22.3 human mRNA for KIAA0958 protein- open reading frame 80U 
PRED5921q22.3 exon prediction onlyU 
COL18A121q22.3 human type XVIII collagenS 
SLC19A121q22.3 human reduced folate carrier (RFC)F 
PRED6021q22.3 exon prediction onlyU 
PRED6121q22.3 exon prediction onlyU 
PCBP321q22.3 poly (rC)-binding protein 3F 
PRED6221q22.3 putative gene containing transmembrane domainF 
COL6A121q22.3 human mRNA for collagen VI alpha-1 C-terminal globular domainS 
PRED6321q22.3 exon prediction onlyU 
COL6A221q22.3 human mRNA for collagen VI alpha-2 C-terminal globular domainS 
FTCD21q22.3EC formiminotransferase cyclodeaminase, EC4.3.1.4ENE
C21orf5621q22.3 spliced EST AA262598U 
LSS21q22.3EC lanosterol synthase EC5.4.99.7ENE
MCM321q22.3 human mRNA for MCM3 import factorU 
C21orf5721q22.3 spliced EST AI702440U 
C21orf5821q22.3 spliced ESTs Z25278/AA825266U 
PCTN221q22.3 pericentrin, kendrin (KIAA0402)T 
KIAA018421q22.3 human mRNA for KIAA0184 proteinU 
S100B21q22.2 S-100 calcium-binding protein, beta chainF 
HRMT1L121q22.3EC2.1.1protein arginine N-methyltransferase 2, EC2.1.1.E 
RPL23AP421q22.3 ribosomal protein L23A pseudogeneP 
   Total enzymes40 
   Total Structural proteins21 
   Total Functional Proteins39 
   Total Transcriptional/Translational/Replication/Regulatory Factors26 
   Total Pseudogenes57 
   Total Unknown102 


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