2011 – 2019 · Bloomington, Indiana

Science's favorite space kitten

Found in a tool shed as the smallest of a feral litter. She had dwarfism, extra toes, no teeth and bones that kept hardening until walking hurt. One person took her home anyway, and years later her fans paid to decode the DNA behind all that magic.

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Lil BUB, a tabby cat with huge green eyes and her tongue sticking out, against a starry galaxy
perma-kitten
22 toes

Patient file

Her vitals.

Her body ignored the textbook. Here is the chart her vets kept, from the tiny frame to the rare gene that explained it.

Adult weight
3.9 lb
Extreme feline dwarfism
Toes
22
Polydactyl, extra digits
Teeth
0
Never grew any
Bone density
High
Osteopetrosis
Tongue
Out
Short lower jaw, 24/7
Mutation
RANK
TNFRSF11A frameshift
  1. 012011

    Born the runt

    Last of a feral litter in Bloomington, Indiana. Bottle-fed, hard to place, nobody expected her to make it.

  2. 022012

    Diagnosed

    A serious health episode led a specialist in Indianapolis to diagnose osteopetrosis. Her bones were growing too dense to move.

  3. 032015

    Sequenced

    Fans crowdfunded the "LilBubome" on Experiment.com. Scientists mapped her genome and found mutations seen in only a handful of humans.

The BUB protocol

By 2012 osteopetrosis had stiffened her so badly she barely left her bed. Her vet suggested an unusual idea: a small pulsed electromagnetic field loop, used every day. A few months later she was chasing toys and climbing furniture. Unusual bodies sometimes need unusual answers, and BUB proved that curiosity can be a kind of medicine.

  • PEMF therapy

    Assisi Loop · daily sessions

  • Osteopetrosis meds

    Bone health · lifelong

  • Genome sequenced

    Funded 2015 · published 2019

  • Specialist vets

    Regular checkups

700K+

Dollars raised for special needs pets

Through Lil BUB's Big FUND, her fans turned internet love into real-world care for animals that shelters struggle to treat and place.

15

Humans share her mutation

Sequencing found a RANK/TNFRSF11A mutation previously seen in just one mouse and fifteen people. A tiny cat from Indiana became a data point for human bone disease research.

Big-screen BUB

“Lil BUB & Friendz” — the documentary following BUB and her internet-famous peers — took home Best Feature Film at the 2013 Tribeca Online Film Festival.
Tribeca Film Festival · 2013

Ask about BUB

The things people always wonder about the space kitten.

Who was Lil BUB?

A one-of-a-kind cat from Bloomington, Indiana. She was the runt of a feral litter and was adopted by Mike Bridavsky, who shared her with the world. She became one of the most beloved animals on the internet.

Why did her tongue always stick out?

BUB had dwarfism and never grew teeth, and her lower jaw was shorter than her upper jaw — so her tongue just hung out. Permanently. Adorably.

What made her so special medically?

She was a “perma-kitten” with 22 toes and a rare bone condition called osteopetrosis, which makes bones abnormally dense. Treatment with a PEMF device helped her walk and play again.

Why was her genome sequenced?

In 2015 fans crowdfunded the “LilBubome” project. Scientists linked her extra toes to a Sonic hedgehog regulatory variant and her osteopetrosis to a frameshift in the RANK/TNFRSF11A gene. The research was published on bioRxiv in 2019.

What is Lil BUB’s Big FUND?

A fund created in partnership with the ASPCA to help special needs pets get the medical care they need — the animals most often passed over in shelters.

How can I help?

Adopt a special needs pet, support your local rescue, or donate in BUB’s name. Every weird, wonderful animal deserves a chance.