A homeless kitten has been found to be neither male or female in what is a veterinary first.
Tabby-and-white Hope was originally thought to be a female cat when it was first admitted to a Cats Protection rescue centre in Warrington.
However vets found no internal or external sex organs.
While vets at the centre said they had seen hermaphrodite cats - with male and female sex organs - they had not seen one with none at all.
Cats Protection's senior field veterinary officer Fiona Brockbank said it appears to be a case of agenesis - the failure of an organ to develop - which she and her colleagues have never seen before.
The charity said examinations have shown Hope will not be otherwise affected by the condition and is waiting to be rehomed at Cats Protection's Tyneside Adoption Centre.
Ms Brockbank said: "We carried out a procedure to look for sex organs but there's nothing apparent inside or out.
"There's an outside possibility of some ectopic ovarian tissue hiding away internally but we think this is extremely unlikely.
"This is so rare that there isn't really a commonly used term for this condition, but it is effectively sexual organ agenesis - where agenesis is the lack or failure of development in relation to body organs."
Ms Brockbank said: "This is not something we've come across before at Cats Protection.
"While this means we don't have any previous cases to base our knowledge of how this will affect Hope in the future, we spent time monitoring this cat to ensure they can urinate and defecate appropriately before they were considered ready for rehoming."
Hope, who is 15 weeks old, is described as a playful kitten which has endeared itself to staff and volunteers at Cats Protection's Warrington Adoption Centre, where it was first admitted and underwent investigations, and the centre in Gateshead.
Tyneside Adoption Centre manager Beni Benstead said: "Discovering Hope's special status has been an exciting time as none of us have seen this before or are likely to again.
"Hope has been a delight to care for and it is fantastic that they are now ready to be adopted.
"We know they will bring someone many years of fun and companionship. We would also be extremely grateful to hear updates on our Tyneside superstar."
Hope was originally brought in with her mother and three siblings by a busy family who did not think they would be able to give them the attention they needed, a Cats Protection spokeswoman said.
Hope has been vaccinated and microchipped and insurer Petplan has confirmed it will not need any special coverage, she said.
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