GRHL1

gene
On this page

Also known as LBP-32MGR

Summary

GRHL1 (grainyhead like transcription factor 1, HGNC:17923) is a protein-coding gene on chromosome 2p25.1, encoding Grainyhead-like protein 1 homolog (Q9NZI5). Transcription factor involved in epithelial development.

This gene encodes a member of the grainyhead family of transcription factors. The encoded protein can exist as a homodimer or can form heterodimers with sister-of-mammalian grainyhead or brother-of-mammalian grainyhead. This protein functions as a transcription factor during development.

Source: NCBI Gene 29841 — RefSeq curated summary.

At a glance

  • GWAS associations: 6
  • Clinical variants (ClinVar): 90 total
  • MANE Select transcript: NM_198182

Identifiers

Gene identifiers

FieldValue
HGNC IDHGNC:17923
Approved symbolGRHL1
Namegrainyhead like transcription factor 1
Location2p25.1
Locus typegene with protein product
StatusApproved
AliasesLBP-32, MGR
Ensembl geneENSG00000134317
Ensembl biotypeprotein_coding
OMIM609786
Entrez29841

Gene structure

Transcript identifiers

Ensembl transcripts: 8 — 3 protein_coding, 3 nonsense_mediated_decay, 2 retained_intron

ENST00000324907, ENST00000405379, ENST00000439493, ENST00000464418, ENST00000472167, ENST00000480736, ENST00000494520, ENST00000497403

RefSeq mRNA: 1 — MANE Select: NM_198182 NM_198182

CCDS: CCDS33144

Canonical transcript exons

ENST00000324907 — 16 exons

ExonStartEnd
ENSE000015620171000059310002277
ENSE0000347286699932079993244
ENSE0000347403399587869958856
ENSE0000347609199549159955101
ENSE0000351360299958799995970
ENSE0000352567099516939951853
ENSE0000353644399906969990747
ENSE0000356778699642359964346
ENSE0000357615799624559962531
ENSE0000359994799638869964042
ENSE0000361083499989659999029
ENSE0000362112199861249986282
ENSE0000363221299610469961436
ENSE0000366658299963169996401
ENSE0000368337099652879965381
ENSE0000369073599920079992146

Expression profiles

Bgee: expression breadth ubiquitous, 220 present calls, max score 99.61.

FANTOM5 (CAGE): breadth broad, TPM avg 2.6984 / max 149.3798, expressed in 717 samples.

FANTOM5 promoters (6 alternative TSS)

Promoter IDTPM avgSamples expressed
187912.0274612
187900.3902233
187930.1929105
187920.051920
187970.01804
187980.01794

Top tissues by expression

250 total, by Bgee expression score (0-100, higher = more expressed):

TissueAnatomy IDExpression scoreQuality
upper arm skinUBERON:000426399.61gold quality
upper leg skinUBERON:000426299.13gold quality
lower esophagus mucosaUBERON:003583498.89gold quality
pharyngeal mucosaUBERON:000035598.40gold quality
gingival epitheliumUBERON:000194998.27gold quality
gingivaUBERON:000182898.17gold quality
mammalian vulvaUBERON:000099798.05gold quality
penisUBERON:000098997.80gold quality
oral cavityUBERON:000016797.79gold quality
skin of hipUBERON:000155497.50gold quality
esophagus mucosaUBERON:000246997.20gold quality
skin of abdomenUBERON:000141697.15gold quality
esophagus squamous epitheliumUBERON:000692096.85gold quality
zone of skinUBERON:000001496.77gold quality
skin of legUBERON:000151196.48gold quality
palpebral conjunctivaUBERON:000181296.13gold quality
oocyteCL:000002395.90gold quality
nasal cavity epitheliumUBERON:000538495.66gold quality
body of tongueUBERON:001187695.37gold quality
mouth mucosaUBERON:000372994.71gold quality
amniotic fluidUBERON:000017394.41gold quality
minor salivary glandUBERON:000183094.21gold quality
secondary oocyteCL:000065594.20gold quality
saliva-secreting glandUBERON:000104494.16gold quality
parotid glandUBERON:000183194.00gold quality
placentaUBERON:000198793.03gold quality
tonsilUBERON:000237292.11gold quality
nasal cavity mucosaUBERON:000182691.76gold quality
tongueUBERON:000172390.56gold quality
vaginaUBERON:000099690.46gold quality

Single-cell (SCXA)

Detected in 2 experiment(s), a significant marker in 2.

ExperimentMarker?Max mean expression
E-MTAB-6819yes233.75
E-ANND-3yes8.82

Regulation

Is transcription factor: yes

Downstream targets (CollecTRI)

2 targets.

TargetRegulation
CYP11A1Unknown
IGF2

JASPAR motifs

MotifNameFamily
MA0647.1GRHL1Grainyhead-related factors
MA0647.2GRHL1Grainyhead-related factors

JASPAR matrix evidence (PMIDs): PMID:18288204

Upstream regulators (CollecTRI, top): HDAC3, MYCN, TFCP2L1

Literature-anchored findings (GeneRIF, showing 14)

  • Includes a comparison to TFCP2L2, the GRHL1 protein. (PMID:12393799)
  • LBP-1b and LBP-9 both stimulate LBP-32/MGR promoter activity. (PMID:18004979)
  • Our findings reveal important pathophysiological differences between human pulmonary fibrosis and specific mouse models of fibrosis and support a crucial role of GRHL2 in epithelial activation in lung fibrosis and perhaps also in epithelial plasticity. (PMID:24375798)
  • A significant role for HDAC3 in the MYCN-mediated repression of GRHL1. (PMID:24419085)
  • Downregulation of miR122 by grainyhead-like 2 restricts the hepatocytic differentiation potential of adult liver progenitor cells. (PMID:25406394)
  • Grhl1 deficiency affects inner ear development in zebrafish. (PMID:25896282)
  • GRHL1, GRHL2, and GRHL3 have roles in cellular proliferation, differentiation, adhesion, and polarity and may promote cancer or be tumor suppressors [review] (PMID:26069269)
  • it was observed that ER stimulated gene expression by interacting with MEIS1 and FOXP3, and ER inhibited gene expression by interacting with THRB and GRHL1. (PMID:27035558)
  • All of these processes involve epithelial-mesencyhmal transition (EMT), MET or a sequence of both, suggesting that the GRHL factors((GRHL1, GRHL2 and GRHL3), could potentially affect tumor initiation and progression via EMT (PMID:28714958)
  • Non-melanoma skin cancer growth is accompanied by coordinated reduced expression of epidermal differentiation genes: GRHL1 and GRHL3, which may be regulated by miR-21-3p and -5p, respectively. Some potentially damaging single nucleotide polymorphisms in GRHL genes occur with altered frequencies in NMSC patients, and they may in particular impair the expression of GRHL3 gene or functioning of encoded protein (PMID:29301499)
  • Structural basis of DNA target-site recognition by grainyhead-like 1. (PMID:29309642)
  • Grainyhead 1 acts as a drug-inducible conserved transcriptional regulator linked to insulin signaling and lifespan. (PMID:35013237)
  • Discovery of a non-canonical GRHL1 binding site using deep convolutional and recurrent neural networks. (PMID:38049725)
  • Vitamin D Receptor Regulates the Expression of the Grainyhead-Like 1 Gene. (PMID:39063155)

Cross-species orthologs

5 orthologs

OrganismSymbolGene ID
danio_reriogrhl1ENSDARG00000061391
mus_musculusGrhl1ENSMUSG00000020656
rattus_norvegicusGrhl1ENSRNOG00000054989
drosophila_melanogastergemFBGN0050011
caenorhabditis_elegansgrh-1WBGENE00001707

Paralogs (5): GRHL2 (ENSG00000083307), TFCP2L1 (ENSG00000115112), TFCP2 (ENSG00000135457), UBP1 (ENSG00000153560), GRHL3 (ENSG00000158055)

Protein

Protein identifiers

Grainyhead-like protein 1 homologQ9NZI5 (reviewed: Q9NZI5)

Alternative names: Mammalian grainyhead, NH32, Transcription factor CP2-like 2, Transcription factor LBP-32

All UniProt accessions (4): B7Z1S6, C9JYY8, Q9NZI5, F8WFB0

UniProt curated annotations — full annotation on UniProt →

Function. Transcription factor involved in epithelial development. Binds directly to the consensus DNA sequence 5’-AACCGGTT-3’. Important regulator of DSG1 in the context of hair anchorage and epidermal differentiation, participates in the maintenance of the skin barrier. There is no genetic interaction with GRHL3, nor functional cooperativity due to diverse target gene selectivity during epithelia development. May play a role in regulating glucose homeostasis and insulin signaling. Functions as a transcription activator. May function as a repressor in tissues where both isoform 1 and isoform 2 are expressed.

Subunit / interactions. Binds DNA as homodimer. Homodimer, also forms heterodimers with GRHL2 or GRHL3.

Subcellular location. Nucleus.

Tissue specificity. Isoform 1 is highly expressed in brain, pancreas, tonsil, placenta and kidney. Isoform 2 is highly expressed in brain and liver. Expressed at very low levels in non-steroidogenic cells.

Post-translational modifications. Methylation at Arg-9 and Lys-116 may be involved in regulating transcriptional activation.

Miscellaneous. GRHL genes (GRHL1, GRHL2 and GRHL3) show a paradoxical lack of redundancy despite their extensive sequence identity in the DNA-binding and protein dimerization domains and the fact that the core consensus DNA binding sites are identical. They have related but remarkably different functions during embryogenesis because of their differential spatiotemporal expression patterns during development.

Similarity. Belongs to the grh/CP2 family. Grainyhead subfamily.

Isoforms (3)

UniProt IDNamesCanonical?
Q9NZI5-11, p70 MGRyes
Q9NZI5-22, p49 MGR
Q9NZI5-33

RefSeq proteins (1): NP_937825* (*=MANE)

Domains & families (InterPro)

IDNameType
IPR007604CP2Domain
IPR040167TF_CP2-likeFamily
IPR057520GRHL1/CP2_CDomain

Pfam: PF04516, PF25416

UniProt features (50 total): strand 16, mutagenesis site 10, sequence conflict 5, splice variant 4, region of interest 4, helix 3, sequence variant 2, turn 2, chain 1, domain 1, compositionally biased region 1, modified residue 1

Structure

Experimental structures (PDB)

3 structures.

PDBMethodResolution (Å)
5MPHX-RAY DIFFRACTION2.34
5MPIX-RAY DIFFRACTION2.35
5MPFX-RAY DIFFRACTION2.92

Predicted structure (AlphaFold)

ModelpLDDTFraction very-high
AF-Q9NZI5-F167.740.38

Functional residue map

Curated UniProt residues grouped by drug-discovery relevance — catalytic, ligand-binding, modification, and mutation-validated positions. Source: UniProtKB sequence features.

Post-translational modifications (1): 208

Mutagenesis-validated functional residues (10):

PositionPhenotype
9increases activity as transcriptional activator.
116reduces activity as transcriptional activator.
378decreases affinity for target dna.
380decreases affinity for target dna.
385decreases affinity for target dna.
421no effect on affinity for target dna.
427loss of activity as transcriptional activator. strongly decreases affinity for target dna.
427loss of activity as transcriptional activator. nearly abolishes affinity for target dna. causes steric hindrance that im
428decreases affinity for target dna.
430decreases affinity for target dna.

Function

Pathways and Gene Ontology

Reactome pathways

1 pathways

IDPathway
R-HSA-1989781PPARA activates gene expression

MSigDB gene sets: 222 (showing top): GOBP_EPITHELIUM_DEVELOPMENT, chr2p25, GOBP_REGULATION_OF_EPIDERMIS_DEVELOPMENT, NKX25_02, GRAESSMANN_APOPTOSIS_BY_SERUM_DEPRIVATION_UP, CHX10_01, GOBP_REGULATION_OF_EPITHELIAL_CELL_DIFFERENTIATION, GOBP_EPIDERMAL_CELL_DIFFERENTIATION, GOBP_CELL_JUNCTION_ORGANIZATION, MARTINEZ_RB1_TARGETS_DN, MCBRYAN_PUBERTAL_BREAST_3_4WK_UP, LASTOWSKA_COAMPLIFIED_WITH_MYCN, MCBRYAN_PUBERTAL_BREAST_5_6WK_UP, GOZGIT_ESR1_TARGETS_UP, GOBP_EPIDERMIS_DEVELOPMENT

GO Biological Process (7): desmosome organization (GO:0002934), regulation of DNA-templated transcription (GO:0006355), regulation of transcription by RNA polymerase II (GO:0006357), epidermis development (GO:0008544), regulation of keratinocyte differentiation (GO:0045616), positive regulation of transcription by RNA polymerase II (GO:0045944), establishment of skin barrier (GO:0061436)

GO Molecular Function (13): transcription cis-regulatory region binding (GO:0000976), RNA polymerase II cis-regulatory region sequence-specific DNA binding (GO:0000978), DNA-binding transcription factor activity, RNA polymerase II-specific (GO:0000981), DNA-binding transcription activator activity, RNA polymerase II-specific (GO:0001228), DNA binding (GO:0003677), DNA-binding transcription factor activity (GO:0003700), chromatin DNA binding (GO:0031490), identical protein binding (GO:0042802), protein homodimerization activity (GO:0042803), sequence-specific DNA binding (GO:0043565), DNA-binding transcription factor binding (GO:0140297), sequence-specific double-stranded DNA binding (GO:1990837), protein binding (GO:0005515)

GO Cellular Component (3): chromatin (GO:0000785), nucleus (GO:0005634), nucleoplasm (GO:0005654)

Reactome top-level categories

Rollup of top-1 pathways:

CategoryPathways
Regulation of lipid metabolism by PPARalpha1

GO top-level categories

Rollup of top GO terms by namespace:

CategoryTerms
RNA polymerase II transcription regulatory region sequence-specific DNA binding3
regulation of DNA-templated transcription2
transcription by RNA polymerase II2
regulation of transcription by RNA polymerase II2
DNA binding2
cellular anatomical structure2
cell-cell junction organization1
DNA-templated transcription1
regulation of gene expression1
regulation of RNA biosynthetic process1
tissue development1
keratinocyte differentiation1
regulation of epidermal cell differentiation1
positive regulation of DNA-templated transcription1
skin epidermis development1
transcription regulatory region nucleic acid binding1
sequence-specific double-stranded DNA binding1
cis-regulatory region sequence-specific DNA binding1
chromatin1
DNA-binding transcription factor activity1
DNA-binding transcription factor activity, RNA polymerase II-specific1
DNA-binding transcription activator activity1
positive regulation of transcription by RNA polymerase II1
nucleic acid binding1
transcription cis-regulatory region binding1
transcription regulator activity1
chromatin binding1
protein binding1
identical protein binding1
protein dimerization activity1
transcription factor binding1
double-stranded DNA binding1
sequence-specific DNA binding1
binding1
chromosome1
intracellular membrane-bounded organelle1
nuclear lumen1

Protein interactions and networks

STRING

974 interactions, top by confidence (×1000):

Protein AProtein BPartner UniProtScore
GRHL1CYP11A1P05108603
GRHL1TGM1P22735521
GRHL1ESRP1Q6NXG1476
GRHL1KLF11O14901475
GRHL1ESR1P03372468
GRHL1OVOL2Q9BRP0465
GRHL1OVOL1O14753461
GRHL1GLIS2Q9BZE0443
GRHL1ESRP2Q9H6T0425
GRHL1ZNF750Q32MQ0421
GRHL1AIREO43918418
GRHL1FOXM1Q08050406
GRHL1ZCCHC24Q8N2G6404
GRHL1DSG1Q02413399
GRHL1IKZF2Q9UKS7390

IntAct

16 interactions, top by confidence:

ABTypeScore
GRHL2GRHL1psi-mi:“MI:0915”(physical association)0.800
GRHL1GRHL2psi-mi:“MI:0915”(physical association)0.800
ZNF76FHL2psi-mi:“MI:0914”(association)0.670
GRHL1GRHL1psi-mi:“MI:0915”(physical association)0.510
Erp44MEN1psi-mi:“MI:0914”(association)0.350
ZNF76GRHL1psi-mi:“MI:0914”(association)0.350
GRHL1POLRMTpsi-mi:“MI:0914”(association)0.350
ARMED6psi-mi:“MI:2364”(proximity)0.270
RAVER1KDM6Apsi-mi:“MI:2364”(proximity)0.270

BioGRID (9): GRHL1 (Affinity Capture-MS), GRHL1 (Affinity Capture-MS), GRHL1 (Affinity Capture-MS), GRHL1 (Two-hybrid), GRHL1 (Reconstituted Complex), GRHL1 (Proximity Label-MS), GRHL1 (Affinity Capture-MS), GRHL1 (Affinity Capture-MS), GRHL1 (Proximity Label-MS)

ESM2 similar proteins: A1L1C7, O08873, O42611, O60716, O94776, O94967, P83094, Q01826, Q0P5J8, Q15542, Q3UHE1, Q3UVG3, Q4R8N2, Q58A45, Q5EY87, Q5JSJ4, Q5M7R9, Q5R7S4, Q5RAR8, Q5TKA1, Q60611, Q640Q5, Q658Y4, Q68FH0, Q6ISB3, Q6NT76, Q6TEP1, Q80U28, Q8BIE6, Q8BJA3, Q8C092, Q8C0V0, Q8C735, Q8C8N2, Q8CGF6, Q8K5C0, Q8N9R8, Q8VI24, Q8WXG6, Q90ZY6

Diamond homologs: G5EDF0, P13002, Q12800, Q3UNW5, Q4V860, Q5EY87, Q5FWH3, Q5M7R9, Q5PPL8, Q5RAR8, Q5RB16, Q6GL65, Q6ISB3, Q6NZH6, Q7T2U9, Q811S7, Q8K5C0, Q8TE85, Q921D9, Q9ERA0, Q9NZI5, Q9NZI6, Q9NZI7

SIGNOR signaling

0 interactions.

Disease & clinical

Clinical variants and AI predictions

ClinVar

90 variants total. Per-class counts are floors (≥ shown; pagination cap):

ClassificationCount (floor)
Pathogenic0
Likely pathogenic0
Uncertain significance66
Likely benign1
Benign1

Top pathogenic / likely-pathogenic (0)

SpliceAI

2899 predictions. Top by Δscore:

VariantEffectΔscore
2:9951842:GGA:Gdonor_gain1.0000
2:9951843:GAG:Gdonor_gain1.0000
2:9951849:GACAA:Gdonor_gain1.0000
2:9951854:GTGA:Gdonor_gain1.0000
2:9951858:G:GGdonor_gain1.0000
2:9953037:G:GTdonor_gain1.0000
2:9953037:G:Tdonor_gain1.0000
2:9954902:A:AGacceptor_gain1.0000
2:9954903:A:Gacceptor_gain1.0000
2:9954910:T:Aacceptor_gain1.0000
2:9954914:GC:Gacceptor_gain1.0000
2:9955099:AAGGT:Adonor_loss1.0000
2:9955100:AGGT:Adonor_loss1.0000
2:9955102:G:GAdonor_loss1.0000
2:9955103:T:Gdonor_loss1.0000
2:9961145:T:TAacceptor_gain1.0000
2:9961433:GGAG:Gdonor_gain1.0000
2:9961434:GAGG:Gdonor_gain1.0000
2:9963882:TTA:Tacceptor_loss1.0000
2:9963883:TAG:Tacceptor_loss1.0000
2:9963884:A:AGacceptor_gain1.0000
2:9963884:A:Cacceptor_loss1.0000
2:9963884:AG:Aacceptor_gain1.0000
2:9963885:G:GTacceptor_gain1.0000
2:9963885:GG:Gacceptor_gain1.0000
2:9963885:GGA:Gacceptor_gain1.0000
2:9963885:GGAA:Gacceptor_gain1.0000
2:9963885:GGAAC:Gacceptor_gain1.0000
2:9963995:G:GTdonor_gain1.0000
2:9964041:GA:Gdonor_gain1.0000

AlphaMissense

4103 scored. Top likely-pathogenic:

VariantProtein changeam_pathogenicity
2:10000595:T:CI582T1.000
2:10000601:T:AV584E1.000
2:10000610:A:TD587V1.000
2:10000630:T:GY594D1.000
2:10000648:T:CF600L1.000
2:10000649:T:CF600S1.000
2:10000650:C:AF600L1.000
2:10000650:C:GF600L1.000
2:10000694:T:CL615P1.000
2:9954991:T:AW33R1.000
2:9954991:T:CW33R1.000
2:9954993:G:CW33C1.000
2:9954993:G:TW33C1.000
2:9955004:T:CL37P1.000
2:9955033:G:CA47P1.000
2:9955037:T:AM48K1.000
2:9955037:T:CM48T1.000
2:9955037:T:GM48R1.000
2:9955040:T:CM49T1.000
2:9955085:T:AL64H1.000
2:9955085:T:CL64P1.000
2:9963906:T:CL256P1.000
2:9963956:T:CY273H1.000
2:9963956:T:GY273D1.000
2:9963960:T:CL274P1.000
2:9963962:A:GN275D1.000
2:9963964:C:AN275K1.000
2:9963964:C:GN275K1.000
2:9963965:A:GK276E1.000
2:9963966:A:TK276I1.000

dbSNP variants (sampled 300 via entrez): RS1000099446 (2:9952230 C>A,G), RS1000140120 (2:9954602 T>C), RS1000232093 (2:9973871 G>A,C), RS1000249529 (2:9980531 G>A,T), RS1000353356 (2:9990399 C>T), RS1000378210 (2:9974520 G>A), RS1000608833 (2:9985075 A>G), RS1000657348 (2:9996947 G>A), RS1000765683 (2:9978712 C>T), RS1000833076 (2:9962829 T>A), RS1000931254 (2:9966270 C>T), RS1000961045 (2:9966576 T>C), RS1000981027 (2:9984711 C>T), RS1000991832 (2:9950401 G>A), RS1001015554 (2:9956231 A>T)

Disease associations

OMIM: gene MIM:609786 | disease phenotypes:

GenCC curated gene-disease

Mondo (0):

Orphanet (0):

HPO phenotypes

0 total (0 of 0 shown, HPO-id order):

GWAS associations

6 associations (top):

StudyTraitp-value
GCST001942_5Prostate cancer3.000000e-08
GCST004988_439Breast cancer4.000000e-10
GCST008062_21Blood urea nitrogen levels1.000000e-10
GCST009267_18Dental caries (decayed, missing and filled teeth)4.000000e-06
GCST009268_1Dental caries (decayed, missing and filled tooth surfaces)5.000000e-06
GCST011320_38Type 2 diabetes or prostate cancer (pleiotropy)4.000000e-08

Drugs & pharmacology

Drug and pharmacology data

Is drug target: no

PharmGKB: 1 entry (VIP=true, CPIC=false)

CTD chemical–gene interactions

61 total (human), top 30 by PubMed support.

ChemicalActions (top 5)PubMed papers
Valproic Acidaffects expression, increases expression, increases methylation7
trichostatin Aincreases expression, affects expression2
arseniteaffects binding, decreases reaction, decreases expression, increases abundance2
sodium arseniteincreases expression, decreases expression, increases abundance2
perfluorooctane sulfonic acidaffects expression, decreases expression2
Acetaminophenincreases expression2
Calcitriolincreases expression2
Estradiolaffects cotreatment, increases expression, decreases expression2
Cyclosporinedecreases expression, increases expression2
Cadmium Chlorideincreases expression2
methylmercuric chloridedecreases expression1
triphenyl phosphateaffects expression1
propionaldehydeincreases expression1
pirinixic acidaffects binding, increases activity, increases expression1
bisphenol Adecreases expression1
titanium dioxideincreases methylation1
2-methyl-4-isothiazolin-3-oneincreases expression1
butyraldehydeincreases expression1
hydroquinoneincreases expression1
mercuric bromideaffects cotreatment, increases expression1
pentanalincreases expression1
antimonitedecreases expression, increases abundance1
CGP 52608affects binding, increases reaction1
perfluoro-n-nonanoic acidincreases expression1
4-(5-benzo(1,3)dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)benzamideaffects cotreatment, increases expression1
abrineincreases expression1
dorsomorphinaffects cotreatment, increases expression1
bisphenol Sincreases methylation1
NSC 689534affects binding, increases expression1
PCI 5002increases expression, affects cotreatment1

Cellosaurus cell lines

2 cell lines: 2 cancer cell line

First 10 cell lines (id-ordered, not curated):

CellosaurusNameCategorySex
CVCL_E1YLHAP1 GRHL1 (-) 2Cancer cell lineMale
CVCL_XP36HAP1 GRHL1 (-) 1Cancer cell lineMale

Clinical trials (associated diseases)

0 trials via MONDO — disease-level, not drug-specific.

  • Disease cohort memberships (association, not causation — diseases whose associated-gene cohort lists this gene; a subset are also under Associated diseases): dental caries