For a Tiffanie, the useful tests are genetic and they are cheap: a buccal swab at 4 weeks for GM1 and GM2 gangliosidosis, a second swab at 8 weeks for pyruvate kinase (PK) deficiency, and an eye exam every 12 months from 12 months of age. None of the three can be cured once signs start, which is why the calendar is built around testing before symptoms rather than imaging after them. Carrier rates in this breed are not published, so treat the schedule as a plan and the risk as unknown; evidence is limited.
Why the swab comes before the scan
GM1 and GM2 gangliosidosis are lysosomal storage diseases: an enzyme is missing, a lipid accumulates in neurons, and the loss is not reversible. A cat that is already ataxic at 5 months has lost neurons that no test will bring back, so the value of the swab is entirely in what it changes before that point — whether to breed, whether to buy, whether to plan for a short life with 6 month checkpoints. The same logic applies to PK deficiency, where the DNA result predicts a hemolytic anemia that may not appear for years, and to PRA, where a fundus exam at 12 months can catch a retina that is thinning before the cat walks into a wall.
GM1 and GM2: swab at 4 weeks, results by 6
Both are autosomal recessive: an affected kitten inherits one variant from each parent, and a carrier shows nothing. Test with a buccal swab at 4 weeks — early enough to sit alongside the first vaccine visit at 6 to 8 weeks — and again if the first sample fails, because a swab taken 30 minutes after nursing can carry maternal cells and give a false genotype. Ask which gene the lab reports: GM1 maps to GLB1 and GM2 to HEXB, and a panel naming neither is not a test for these diseases. For a breeding cat, test before the first mating, not after the litter is born; two carriers mated together have a 1 in 4 chance of an affected kitten per pregnancy. Signs usually appear in the first year: a wide-based gait, a fine head tremor at rest, an exaggerated startle to a dropped spoon, and a stare that does not track a toy.
PK deficiency: swab at 8 weeks, CBC every year
PK deficiency is also recessive and also silent in carriers. Swab at 8 weeks, when the kitten is stable enough for a full panel, and add a CBC with a reticulocyte count at the same visit; a PCV under 25 percent with a reticulocyte count above 60,000 per microlitre in a young cat is the pattern worth chasing. From 12 months, a CBC once a year is the cheap screen, because the anemia can be intermittent and a single normal value at 14 months proves little. Avoid repeating vaccines in an anemic cat until the PCV is back above 28 percent, and tell any surgeon the genotype before anesthesia. A cat with PK deficiency tolerates hemolysis badly, and a 2 day stay for a dental can turn into a transfusion.
PRA: the dim-light test at 12 months
Progressive retinal atrophy starts in the rods, so the first sign is night vision, not blindness: a cat that hesitates at a dark doorway at 18 months, or walks with its whiskers forward, is showing it. A fundic exam by an ophthalmologist every 12 months from 12 months of age is the screen; a DNA test covers some forms only, so confirm which variant the laboratory reports before you believe a clear result. Electroretinography at 200 to 400 USD is the confirmatory step when the fundus looks normal but the behavior does not. No drug reverses the storage disease; seizure control is anticonvulsant class, by vet prescription. There is no treatment; the point is to stop breeding the line and keep the cat indoors after dusk, where a 30 percent loss of rod function matters less.
The schedule in one table
| Age | Test | Sample | Repeat |
|---|---|---|---|
| 4 weeks | GM1 (GLB1) and GM2 (HEXB) | Buccal swab | Once, or if sample fails |
| 8 weeks | PK deficiency (PKLR) plus CBC | Swab and 0.5 mL blood | Once |
| 6 months | Neurologic and gait check | Exam | Every 6 months to 2 years |
| 12 months | Fundic exam, echocardiogram | Exam and ultrasound | Every 12 months |
| 12 months onward | CBC with reticulocytes, urinalysis | 1 mL blood, urine | Every 12 months |
| Before breeding | Full panel on both cats | Swab | Once per cat |
Four signals to watch at home
- Dim light. Hesitating at a doorway after sunset, bumping a chair leg it cleared last month, or refusing stairs it used to take.
- Gait and tremor. A wide stance, a head tremor that appears when the cat sits still, or a startle that lasts 5 seconds after a cupboard closes.
- Gum colour. Pale pink turning white, or a yellow tinge at the gum line and the inside of the ear, checked weekly in daylight.
- Stamina. Stopping halfway up 12 steps, sleeping through a meal, or a resting rate above 40 per minute after 10 minutes of rest.
Hour-level thresholds
| Sign | Trigger value | Act within | Setting |
|---|---|---|---|
| Seizure or collapse | Any, first episode | 0 hours | Emergency |
| Gums white or yellow | Any, with weakness | 0 to 2 hours | Emergency |
| Sudden blindness | Both eyes, under 24 hours | 24 hours | Ophthalmology |
| Tremor or ataxia | New, or worse over 7 days | 7 days | Neurology |
| Resting respiratory rate | 40 or more per minute | 2 hours | Emergency |
| Refusing food | 24 hours in a cat under 2 kg | 12 hours | Clinic |
Costs, USD and CNY
| Item | USD | CNY | Interval |
|---|---|---|---|
| GM1 or GM2 single variant | 60 to 120 | 430 to 870 | Once |
| Full DNA panel, 4 to 6 variants | 150 to 300 | 1080 to 2160 | Once |
| PK deficiency plus CBC | 110 to 210 | 790 to 1510 | Once |
| Ophthalmology exam with fundus | 80 to 150 | 580 to 1080 | 12 months |
| Electroretinography | 200 to 400 | 1450 to 2900 | If indicated |
| Echocardiogram with report | 250 to 450 | 1800 to 3250 | 12 months |
Ranges are 2026 laboratory and clinic prices in the US and Chinese tier-1 cities at 7.2 CNY per USD; a swab panel is the cheapest item on the list and the only one that changes a breeding decision.
Five steps for this month
- Order the GM1 and GM2 swab now if the cat is 4 weeks or older; age does not change a genotype.
- Add PK and a CBC to the 8 week visit, and keep the printed result with the vaccine card.
- Book the 12 month fundic exam and echo on the same day, so one car trip covers both.
- Photograph the gums in daylight this week, then monthly, and compare the colour, not the mood.
- Ask both parents' genotypes before agreeing to a litter; two carriers mean a 1 in 4 risk per kitten.
For a line with a longer screening record, compare the Tonkinese schedule; the cardiac side of the 12 month visit follows the Turkish Van plan. Choosing between breeds on health grounds starts with the breed quiz.
Terms mentioned in this article
Frequently asked
Can I test for GM1 and GM2 after the kitten is already walking badly?
You can, but the result no longer changes the outcome, only the explanation. The value of a 4 week swab is that it lands before the first tremor, so a carrier is never bred and an affected kitten gets 6 month checkpoints instead of an emergency CT. Once ataxia is present, neurons are already lost, and no test or supplement reverses a lysosomal storage disease.
Does a clear PK test mean I can stop doing blood work?
No, keep the yearly CBC from 12 months. A clear genotype removes the inherited cause, but anemia in a cat has many others, and the PK result says nothing about them. A PCV under 25 percent with reticulocytes above 60,000 per microlitre still needs a workup, and repeating vaccines in an anemic cat waits until the PCV is above 28 percent.
Is the DNA test for PRA enough on its own?
Only for the variants the laboratory actually reports. Several forms of progressive retinal atrophy have no published DNA marker, so a clear result on one variant does not exclude the disease. Pair the swab with a fundic exam every 12 months from 12 months of age, and add electroretinography at 200 to 400 USD if the behavior suggests night blindness while the fundus still looks normal.