Table 1.
Therapeutic strategies to restore hearing and balance in mouse models of deafness and vestibular dysfunction*.
| Common gene name (human gene symbol; deafness locus) | Mouse model | Mutant allele | Therapeutic strategy | Gene or drug delivered | Type of injection | Age at delivery | Phenotypic analyses |
|---|---|---|---|---|---|---|---|
| Vesicular glutamate transporter 3 (SLC17A8; DFNA25; Ruel et al., 2008) | Vglut3 KO (Seal et al., 2008) | EGFP/Neo cassette into exon 2 | gene replacement | AAV2/1-Vglut3 | RWM or cochleostomy | RWM: P1–P3, P10–P12; cochleostomy: P10–P12 | RWM: P1–P3†: ABR, CAP, acoustic startle (Akil et al., 2012) |
| Harmonin (USH1C; DFNB18; Ahmed et al., 2002; Ouyang et al., 2002) | Ush1c knock-in (Lentz et al., 2010) | French-Acadian c.G216A | gene augmentation | AAV2/Anc80L65.CMV.harmonin-b1 (Landegger et al., 2017) | RWM | P0–P1; P10–P12 | P0–P1†: MET, ABR, DPOAE, acoustic startle (Pan et al., 2017) |
| gene augmentation by correction of pre-mRNA splicing | ASO-29 | IP | P3–P16 | P5†: ABR; P3–13†: open field, rotations/sec (Lentz et al., 2013) | |||
| IP | Single dose: P1, P5, or P7; multiple doses: P1, 3; P1, 3, 5, 7 | P5†: ABR and DPOAE (Ponnath et al., 2017) | |||||
| IP | P1; P3–P5; P4/5; P1, 3, 5, 7; P15 | P1†: VsEPs (Vijayakumar et al., 2017) | |||||
| TMI into amniotic cavity | E13-E13.5 | pre-mRNA splicing correction (Depreux et al., 2016) | |||||
| Transmembrane channel-like 1 (TMC1; DFNB7/11 for Tmc1Δ and DFNA36 for Tmc1Bth/+; Kurima et al., 2002) | Tmc1Δ (Kawashima et al., 2011) | LacZ/Neo cassette deleting exons 8 and 9. | gene replacement | AAV2/1-Tmc1; AAV2/1-Tmc2 | RWM (bulla intact) | P0–P2 | MET, ABR, DPOAE (Askew et al., 2015) |
| Tmc1Bth/+ (Vreugde et al., 2002) | Beethoven; missense mutation: p.M412K, c.T1235A | knockout of autosomal dominant disease allele | S. pyogenes Cas9–sgRNA ribonucleo–Protein complexes | Cochleostomy or posterior canalostomy | P0–P2: cochleostomy (Tmc1Bth/+); 6 wk: canalostomy (Atoh1-GFP) | MET, ABR, DPOAE, acoustic startle (Gao et al., 2018) | |
| knockdown of autosomal dominant disease allele | AAV2/1 and AAV2/9 vectors encoding artificial siRNA and eGFP | RWM | P0–P2 | MET, ABR, DPOAE (Shibata et al., 2016) | |||
| Lipoma HMGIC fusion partner-like 5/tetraspan membrane protein of hair cell stereocilia (LHFPL5; DFNB66/67; Tlili et al., 2005; Kalay et al., 2006; Shabbir et al., 2006) | Lhfpl5 KO (Longo-Guess et al., 2007) | LacZ/Neo cassette deleting exons 1 and 2 (van Wijk et al., 2006) | gene replacement | Exosome-AAV2/1-Lhfpl5 | RWM (György et al., 2017) | P1–P2 | ABR, head tossing, circling (György et al., 2017) |
| Scaffold protein containing Ankyrin repeats and SAM domain (SANS; USH1G; Mustapha et al., 2002; Weil et al., 2003) | Ush1G KO (Caberlotto et al., 2011) | Sans null: Ush1Gfl/fl crossed to PGK-Cre | gene replacement | AAV2/8-Sans-IRES-GFP | RWM | P2.5 | ABR, circling, VOR (Emptoz et al., 2017) |
| Whirlin (WHRN; DFNB31; Ebermann et al., 2007) | Whirler KO (Whrnwi/wi; Lane, 1963; Holme et al., 2002) | 592 base pair deletion between exons 6–9 | gene replacement | AAV2/8-whirlin | Posterior canalostomy | P0–P5 | ABR, VsEP, open field, RotaRod, swim (Isgrig et al., 2017) |
| Clarin 1 (CLRN1; USH3; Sankila et al., 1995; Joensuu et al., 2001) | KO-TgAC1 (Geng et al., 2012) | Clarin 1 KO with Clrn1 expression from Atoh1 3’enhancer/β-globin promoter | gene augmentation | AAV2-smCBA-Clrn1 and AAV8-smCBA-Clrn1 with or without Clrn 1 UTRs | RWM | P1–P3 | click stimulus ABR (Geng et al., 2017) |
| Tg;KIKI (Alagramam et al., 2016) | Knock-in of human p.N48K into Clrn1 locus and Clrn1 expression from Atoh1 3’enhancer/β-globin promoter | Small molecule stabilizer of CLRN1N48K | BioFocus 844 | IP | P10–P45 (dose escalation paradigm); P30–P45 | P10–P45† (ABR; Alagramam et al., 2016) | |
| Clrn1 KO (Clrn1ex4−/−) and conditional KO (Clrn ex4fl/fl Myo15-Cre+/−) (Dulon et al., 2018) | Clrn1 KO: Clrn ex4fl/fl crossed to PGK-Cre; Conditional KO: Clrn ex4fl/fl crossed to Myo15-Cre+/− | gene replacement | AAV2/8-Clrn1-IRES-GFP | RWM | P1–P3 | ABR (Dulon et al., 2018) | |
| Methionine sulfoxide reductase B3 (MSRB3; DFNB74; Waryah et al., 2009; Ahmed et al., 2011) | MsrB3 KO (Kwon et al., 2014) | MsrB3 exon 7 replaced with Neo cassette | gene replacement | AAV2/1-MsrB3-GFP | TMI into otic vesicle | E12.5 | ABR (Kim et al., 2016) |
| Connexin 30 (GJB6; DFNB1B (Del Castillo et al., 2003) | Cx-30 KO (Teubner et al., 2003) | Cx-30 gene replaced with NLS-β-galactosidase | gene replacement | pCMV-Cx-30-GFP | TMI into otic vesicle with electroporation | E11.5 | ABR (Miwa et al., 2013) |
| shRNA-Cx-30 in wild type mice | Cx-30 knock down by four shRNAs | gene augmentation | pU6-shRNAs and pCMV-shRNA-resistant Cx-30 | TMI into otic vesicle with electroporation | E11.5 | ABR (Miwa et al., 2013) | |
| Connexin 26 (GJB2; DFNB1) (Guilford et al., 1994; Kelsell et al., 1997) | Conditional Cx26 KO (Wang et al., 2009) | Cx26 null: Cx26fl/fl (exon 2) crossed to Foxg1-Cre | gene replacement | AAV2/1-CB7-Gjb2 and AAV2/1-CB7-Gjb2-GFP | Cochleostomy | P0–P1 | ABR (Yu et al., 2014) |
| RE1-silencing transcription factor (REST; DFNA27) (Peters et al., 2008) | Rest+/∆Ex4 (Nakano et al., 2018) | Rest+/flEx4 crossed to Gfi1+/Cre or Rosa+/CreERT2 | HDAC inhibitors | SAHA (Vorinostat) | Subcutaneous injection | P7–P15, daily. | ABR (Nakano et al., 2018) |
*Abbreviations: AAV, adeno-associated virus; ABR, auditory brainstem response; ASO, antisense oligonucleotide; Atoh1, atonal homolog 1; Bth, Beethoven allele; CAP, compound action potential; cDNA, complementary deoxyribonucleic acid; CMV, cytomegalovirus; Cre, Cre recombinase; DFNA, autosomal dominant nonsyndromic hearing loss; DFNB, autosomal recessive nonsyndromic hearing loss; DPOAE, distortion product otoacoustic emissions; E, embryonic day; fl, flanked by loxP sites (floxed); GFP, enhanced green fluorescent protein; IP, intraperitoneal; IRES, internal ribosomal entry site; KO, knockout; LacZ, β-galactosidase; mRNA, messenger ribonucleic acid; MET, mechanotransduction; Neo, neomycin; NLS, nuclear localization signal; p, plasmid; P, postnatal day; RWM, round window membrane; smCBA, small chick β-actin promoter; Tg, transgene; TMI, transuterine microinjection; PGK, phosphoglycerate kinase; shRNA, short hairpin ribonucleic acid; sgRNA, small guide ribonucleic acid; siRNA, small interfering ribonucleic acid; UTR, untranslated region; VOR, vestibulo-ocular reflex; VsEP, vestibular sensory evoked potential. †the age(s) at delivery that produced maximal therapeutic benefit.