Have you been pining for a "teacup" pig but worried that the supposedly petite porcine pet might grow as big as your bathtub? A Chinese biotech firm says it now has the answer: a genetically modified swine that tops out around 15 kilograms. BGI, a company based in the southern city of Shenzhen that is known for its work sequencing human, plant and animal DNA, recently announced that it intends to start selling $US1600 miniature pigs that it initially created as laboratory models for studying human ailments.