Rex Syrians

by Nichole Royer


Although Rex Syrian hamsters have been common in Europe for many years, they are a fairly recent import into North America. In 2003 a number of Rex and Rex carrier hamsters were shipped from Sweden in two different shipments, with animals ending up on  the West Coast and in the Midwest of the United States as well as in Canada. First generation pups are also on the East Coast and in other areas of the U.S. On the West Coast two Cream Rex males were imported, as well as carriers in Cream, Dark Gray, and other colors. These animals have been bred together, and into existing stock, and the numbers of Rex hamsters in this country are quickly growing and moving into other regions.

There was a previous occurence of a rex-like gene in the United States.  In the spring of 2001 a petowner in Brooklyn, NY bred two pet store Blacks that were believed to be siblings.  The litter contained mostly normal-coated Blacks, but also three DEWs, two of which had sparse, velvety fur and crinkled whiskers.  These two, a male and a female, were obtained by The River Road Hamstery.  They had all the appearance of a poor rex-like coat which tended to large ventral areas of baldness.  The line was carried to four generations.  None of the females could lactate to support a litter.  The males when outcrossed produced healthy normal-coated progeny.  Despite outcrossing, the breeding of carriers resulted in no improvement in the coats of the subsequent rexes.

It is possible that the Rex allele was carried in this Black line since the importation of the color from Europe.  It seems more likely that it was a new mutation that appeared in an inbred line.  The phenotype indicated that the gene probably was not the same as the known Rex gene, but may have had more in common with Fur Deficiency which has been confined to laboratory populations.  This article will only discuss the Rex gene imported from Europe, the gene for which the BHA and NHC standards have been written.


Probably the most consistent trait of the Rex gene is to cause curled, crimped, or wavy whiskers. Ideally this gene also causes a curled or wavy coat. It will appear more tightly curled, frizzy, and plush in shorthaired hamsters. Long haired Rex will have a wavy and more lifted coat but may also appear somewhat scruffy (particularly males with good coat length).

Rex can be combined with any color, marking or coat type. According to the BHA standard, "The color and markings shall conform to the recognized color standard, allowing for the rex coat which will dilute color slightly."

The BHA standard describes the Rex coat as being "soft and dense, and evenly frizzy." As with any standard this describes the ideal, and in truth Rex hamsters can range from having tight curls, to slight waves. Some have no curl at all and would be indistinguishable from non-Rex if it weren't for their whiskers.

When is a Rex not a Rex?

Can you tell the Rex from the Non-Rex?
It's not necessarily easy to identify the Rexes, and those who have not worked with the gene often find it difficult to identify them.  The first and third row contain Rex syrians. The second and fourth row are Non-Rex syrians. As you can see, the Rex gene does not have a monopoly on causing a waved or curled coat. It's not unusual for standard coated hamsters, particularly those with exceptionally thick nice coats, to have a considerable amount of wave. The big difference, and the key to knowing you are dealing with the Rex gene, is curled whiskers. Non-rex hamsters will not have curly whiskers, no matter how wavy their coat is. And on the flip side, a poor Rex may have so little curl that the only way to detect the presence of the rex gene is those curly whiskers.  The Rex coat can also have a different appearance at different times.
REC Rex Pup
These two photos show the same Rex female at different ages.  Most people would miss the fact that she is a Rex if they were to see only the photo to the right.
Rex Whiskers
Rex Whiskers
These photos show the curly whiskers which are characteristic of the Rex gene.  The length and curliness of the whiskers varies, but they are distinct from the straight whiskers of the normal coated Syrian.
Showing Rex

Rex is not a variety that is the best choice for the novice shower or the exhibitor looking for a quick or simple path to success. Rex adds one more complication to an already complex combination of color, type, and coat -- and one more way for a hamster to loose points. In order to do well on the show bench, a good Rex needs to combine excellent type, proper color, correct coat length and density, as well as nice curl.

On the show bench the judge will be evaluating the coat for both its curliness and density. In both cases more is better.

Short haired Rex are often the most curly in appearance and are more plush looking. This is most noticeable on their heads as compared to their standard coated counterparts. Long haired Rex females are less curly, but still retain a plush or frizzy look.
These are two Golden short-haired brothers.
Can you tell the Rex brother from the non-Rex brother?
Long Haired Rex males who have proper length to their coats are a different story all together. Their hair is more wavy than curly and can often be scruffy or unkempt looking. You can see their curl best on their heads, and of course in their whiskers.

Keeping a Long Haired male Rex's coat in show condition can be quite a challenge. Not only does that beautiful long coat tangle, but the wave provided by the Rex gene causes the coat to wrap around bits of bedding which have rough edges. In the United States we have discovered that nicely coated males kept on typical aspen shavings lose considerable density due to their coat catching on their bedding and being pulled out. The Care Fresh products proved to be as much if not more of a problem. In the end pelleted aspen seems to be an ideal choice for retaining coat, but not very comfortable for the animal. Alpha-dri, a paper laboratory product, stands out as a very good compromise. Being cut in small square bits it has no rough edges to catch in the coat, but is soft enough to provide for the hamsters comfort. It is rather expensive however. Naturally in a non-showing pet situation the coat can just be neatly trimmed to eliminate this whole problem all together.

Rex can also be combined with Satin and appears to be very pretty. In a variety which already has density issues, however, Satin should be added to the equation with caution since it tends to cause the appearance of a thinner coat.

Rex can also be combined with any color or pattern. It is not unusual for the color to appear diluted in a Rex coat. Self colored animals will show this dilution less than those who are agouti, and in agouti animals it can be expected that the tipping on the hair will be noticeably affected. This is noted in the standard and the judge will take it into account when judging. This is not to say that one should not strive for ideal undiluted color however.

Because it causes a change in the lay of the coat, Rex will effect the appearance of markings. It can disrupt and blur even lines, and cause the appearance of brindling on solid spots. This does not make Rex the ideal coat for showing Dominant Spot, Recessive Dappled, or Tort/Tri colored hamsters.

Breeding Rex

Rex is a simple recessive gene (rx). In order for a hamster to be Rex, it must inherit the gene from both parents. Two Rex hamsters, when bred together, will produce a litter of all Rex pups. A Rex bred to a non-rex (who does not carry Rex) will produce a litter of non-Rex pups, however they will all carry Rex. If those pups are in turn bred to each other, to other Rex carriers, or to a Rex, they will produce Rex offspring. Thus it is very easy to combine Rex with any other color, marking, or coat type.

Rex pups can easily be spotted in the nest as early as a couple days of age.  Even before fur and pigment are really evident, those curly/wavy whiskers will be obvious and easily seen. As the pups become older the Rex youngsters will have coats which appear wavy and perhaps somewhat scruffy in comparison to their non-rex littermates. At weaning (4 weeks) the pups coats will be about as curly as they are going to get. One of the easiest ways to pick the curliest is to look at their whiskers. The more curled the whiskers the more curled the coat is likely to be.

When breeding for a good Rex, coat is essential to focus on both coat curl and coat density. These characteristics can actually work against each other, so achieving the right balance should be the goal. Curl is created due to a flattening of the hair. The more flattened, the more curl. The more flattened the less dense the coat often appears however. Thus even in a line with nicely dense standard coats, a Rex may appear to lack density. Tradition has shown that periodic outcrossing to lines of non-rex with nice density is one of the best ways to retain density while still achieving adequate curl.

When choosing breeding stock out of a litter, you will want to narrow your choices to the ones showing the most curl. Once again, the whiskers can be a good indicator or potential. When evaluating adult animals, your best breeders are of course those animals who show the most curl or wave to their coats.  Ideally those who have little curl should be avoided unless they excel in other areas.

And of course, breeding for curly coats is not all there is to having nice Rex.  As with any other feature, a curly coat is only one piece of the puzzle. Equally important (perhaps more so in fact) is correct color/markings, proper coat length and density, and good type. No matter how curly or nicely colored, a Rex with poor type is not a good breeding choice.

Rex is not an ideal choice for a novice breeder or one looking for a quick or simple path to producing really nice hamsters. The coat adds a huge challenge in addition to trying to breed for nice type, proper coat length and density, and correct color. Curl is one more feature which has to be selected for, and one more characteristic that has to be taken into consideration when choosing potential breeding stock. The more features that have to be factored in, the slower a breeding program will go. Thus Rex is a variety for those dedicated to putting in the time it takes to get it right.

The myth of the "Rare Rex"

There is a growing myth in the U.S. that Rex hamsters are in some way rare and therefore extremely valuable. Let me make it clear that the Rex gene, while currently new in the United States, is in no way rare or exceptionally valuable.  This gene is very simple to reproduce, and can easily be combined with any color, marking, or coat type. While it is a new gene to this continent, it is quickly spreading, and dedicated fanciers are seeing to it that pups are available. Responsible breeders are selling Rex hamsters for prices well within the ranges seen for every other variety, usually in the $10-$20 price range depending on the overall quality of the animal. Please don't be taken in by irresponsible individuals selling Rex hamsters for exorbitant prices and attempting to market them as rare.
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