Spinal Muscular Atrophy Mouse Model Resource

Use this resource to identify and select the most appropriate mouse model of SMA for your research and to obtain a guide to help you efficiently work with these mice.

Comparison of featured SMA models

This table summarizes the differences between important mouse models for SMA to help you easily find the right strain for your research

Strain Name

Common Name

Molecular Mutation

Phenotype

Survival

FVB.Cg-Tg(SMN2)89Ahmb Smn1tm1Msd/J

005024

Burghes’ Severe Model Combines a knockout of mouse Smn1 (caused by insertion of a lacZ reporter) with a transgene that carries one normal copy of human SMN2 Double homozygotes show vacant or partially occupied motor endplates, abnormal neurofilament protein accumulations in presynaptic motor neurons, decreased muscle fiber diameter, low body weight, and respiratory distress Stillborn or die by postnatal days 4-6

FVB.Cg-Tg(SMN2*delta7)4299Ahmb Tg(SMN2)89Ahmb Smn1tm1Msd/J

005025

SMNdelta7 or Moderate Type II SMA mice Triple mutant contains a knockout of mouse Smn1 (caused by insertion of a lacZ reporter) and two transgenes, one with a single normal copy of human SMN2 and the second with a human SMN2 promoter and a human SMN2 cDNA that lacks exon 7 (SMNdelta7) Triple homozygotes have decreased body weight and impaired righting response at P5, have abnormal gate and impaired balance and limb coordination by P10, and skeletal muscle fiber atrophy and abnormal cardiac morphology and function by P14 Death by postnatal days 15-22 (mean survival of 17.7 days)

FVB.Cg-Tg(SMN2)2Hung Smn1tm1Hung/J

005058

SMA-like mice line 2 Double mutant containing a knockout (deletion of exon 7) in mouse Smn1 and a transgene expressing normal human SMN2 Double homozygotes have thickened tails but are otherwise normal, mice homozygous for Smn1tm1Hung and hemizygous for Tg(SMN2)2Hung have selective loss of thick myelinated motor neurons, decreased motor neuron number, and axon degeneration in spinal cord, muscular atrophy, and hindlimb paralysis Double homozygotes have normal life span Mice homozygous for Smn1tm1Hung and hemizygous for Tg(SMN2)2Hung die by postnatal days 15-16

FVB.129(B6)-Smn1tm5(Smn1/SMN2)Mrph/J

008604

Smn allele C Expresses a targeted knock-in mutation containing two coding sequences; the first encodes a hybrid gene in which mouse Smn1 exons 7 and 8 were replaced by human exons 7 and 8, and the second encodes a full-length human SMN2 gene Homozygotes exhibit tail necrosis, low body weight, diminished grip strength, and lower bone mineral content and density with age Normal life span

STOCK Smn1tm3(SMN2/Smn1)Mrph Tg(SMN2*delta7)4299Ahmb Tg(SMN2)89Ahmb/J

007951

Smn1 COIN (conditional inversion) Triple mutant containing a conditional knock-in allele and two transgenes: one Tg with a single normal copy of huSMN2, a second Tg with a huSMN2 promoter and a huSMN2 cDNA lacking exon 7 (SMNdelta7), and a floxed knock-in allele that prior to breeding to a Cre driver strain, expresses a hybrid Smn1 gene containing mouse Smn1 exons 1 through 6 and huSMN2 exons 7 and 8; following Cre-mediated recombination, the allele is "rescued", and the mice express mouse Smn1 exons 1 through 7 and huSMN2 exon 8 Prior to Cre-mediated recombination mice have a phenotype similar to strain 005025 and post Cre-mediated recombination mice express fully functional Smn1 and the phenotype is rescued if recombination occurs prior to postnatal day 8 Prior to Cre-mediated recombination, death by postnatal days 15-22 (mean survival of 17.7 days)

Featured JAX® Mice Models of SMA

FVB.Cg-Tg(SMN2)89Ahmb Smn1tm1Msd/J

005024

  • Common name: Burghes’ Severe Model
  • Genetic background: FVB/N; incipient congenic (N5)
  • Double mutant contains a knockout of mouse Smn1 (caused by insertion of a lacZ reporter) and a transgene with one normal copy of human SMN2 (Monani et al. 2000)
  • Affected mice exhibit abnormal muscular innervation, motor neuron degeneration, tremors, abnormal suckling behavior
  • Mortality: stillborn or death by postnatal days 4-6

FVB.Cg-Tg(SMN2*delta7)4299Ahmb Tg(SMN2)89Ahmb Smn1tm1Msd/J

005025

  • Common name: SMNdelta7 or Moderate Type II SMA mice
  • Genetic background: FVB/N; incipient congenic (N6)
  • Triple mutant contains a knockout of mouse Smn1 (caused by insertion of a lacZ reporter) and two transgenes, one with a single normal copy of human SMN2 and the second with a human SMN2 promoter regulating expression of human SMN2 cDNA that lacks exon 7 (SMNdelta7) (Le et al. 2005)
  • Affected mice exhibit abnormal muscular innervation and neuromuscular synapse morphology, impaired righting response by postnatal day 5 (P5), abnormal gate and impaired balance and limb coordination by P10, and  skeletal muscle fiber atrophy by P14
  • Mortality: death by postnatal days 15-22 (mean survival of 17.7 days)

FVB.Cg-Tg(SMN2)2Hung Smn1tm1Hung/J

005058

  • Common name: SMA-like mice line 2
  • Genetic background: FVB/N; fully congenic (N10)
  • Double mutant containing a knockout (deletion of exon 7) in mouse Smn1 and a transgene expressing normal human SMN2 (Hsieh-Li et al. 2000)
  • Double homozygotes have thickened tails and otherwise normal phenotype
  • Mice homozygous for Smn1tm1Hung and hemizygous for Tg(SMN2)2Hung exhibit abnormal motor neuron morphology, decreased motor neuron number, muscular atrophy, and hindlimb paralysis
  • Mortality in mice homozygous for Smn1tm1Hung and hemizygous for Tg(SMN2)2Hung: death by postnatal days 15-16

FVB.129(B6)-Smn1tm5(Smn1/SMN2)Mrph/J

008604

  • Common name: Smn allele C
  • Genetic background: FVB/NJ (001800); fully congenic using speed congenic protocol (N8)
  • Expresses a targeted knock-in mutation containing two coding sequences; the first generates a mouse:human hybrid protein in which mouse Smn1 exons 7 and 8 were replaced by human exons 7 and 8, and the second is a full copy of the human SMN2 gene (Osborne et al. 2012)
  • Homozygotes exhibit tail necrosis, low body weight, diminished grip strength, and lower bone mineral content and density with age
  • Normal life span

STOCK Smn1tm3(SMN2/Smn1)Mrph Tg(SMN2*delta7)4299Ahmb Tg(SMN2)89Ahmb/J

007951

  • Common name: Smn1 COIN (conditional inversion)
  • Genetic background: mixed; containing FVB/N, 129S6/SvEvTac, and C57BL/6NTac
  • Harbors two transgenes, one with a single normal copy of human SMN2 and the second with a human SMN2 promoter and a human SMN2 cDNA  that lacks exon 7 (SMNdelta7)
  • Harbors an Smn1floxed allele that prior to breeding to a Cre driver strain, expresses a hybrid Smn1 gene containing mouse Smn1 exons 1 through 6 and human SMN2 exons 7 and 8, and following Cre-mediated recombination (inversion), the allele is "rescued" into a format that contains mouse Smn1 exons 1 through 7 and human SMN2 exon 8 (Lutz et al. 2011)
  • Prior to Cre-mediated recombination, has a phenotype similar to strain 005025
  • Post Cre-mediated recombination, expresses fully functional Smn1 and phenotype is rescued if recombination occurs prior to postnatal day 8