Table 1 Comparison of methods used for gene delivery to the mouse brain

Retro-orbital injection

Retina

Retina and brain

Direct route to the brainbypassing the BBB; efficient and effective for delivering drugs

Disruptive to the pups;

potential vision damage;

possible anesthesia's systemic effect;

special training on anaesthetization

[1, 2]

Intravenous injection

Tail vein

Brain and other tissues

No special equipment needed

Injected substance needs to be able to cross the BBB;

larger volumes of virus needs; low transgene expression; diffusion to other tissues; laborious to perform; high failure rate

[3]

In-vivo electroporation

Ventricle/desired brain parenchyma

Whole brain or specific brain region

Direct delivery of DNA;

strong expression of transgenes;

rapid and efficient

Need optimization;

specialized voltage for widespread delivery;

high cost;

germline modifications;

surgical procedures

[7,8,9]

Intravascular injection

Temporal facial vein

CNS and peripheral organs

Stable and global transgene expression;

efficient;

minimal stress and quick recovery

Specialized handling skill;

possible damage to BBB;

injected substance needs to be able to cross the BBB

[15]

Transverse sinus

Transverse sinus

Whole brain

Efficient; fast and simple;

less equipment

Specialized handling skill;

not enough applications

[14]

Intracerebroventricular injection

Ventricular system

Whole brain

Can be adapted for cell type-specific expression;

direct delivery into the mouse brain;

no need to cross the BBB;

cost-effective; rapid; no surgery needed; no undesirable side effects in neonatal mice; quick recovery in neonatal mice

Non-uniform expression across the brain

[11, 16, 17]

Current study