Fading Gene in Shih Tzus: Understanding Coat Color Changes

When you bring home a rich, chocolate-colored Shih Tzu puppy, it’s easy to fall in love with their striking, deep brown coat. But what happens when that deep chocolate starts to fade over time? It can come as a surprise to new owners when their once-dark puppy transforms into a lighter shade of milk chocolate, café au lait, or even beige. So what’s really going on?

Let’s break it down in a clear and helpful way, especially if you’re searching for a Shih Tzu that keeps that stunning liver color into adulthood.

First, what is the liver color in Shih Tzus?

In genetics, liver isn’t just a color, it’s a gene expression. The liver (or chocolate) coloring in Shih Tzus is caused by a recessive gene at the B locus, specifically the TYRP1 gene. When a dog inherits two copies of the recessive allele (bb), it will display liver pigmentation. This includes liver-colored noses, paw pads, eye rims, and of course, that chocolate-toned coat.

This part is important… because it is testable. You can confirm through DNA testing that your Shih Tzu carries or expresses the liver color gene.

But here’s where it gets tricky → not all liver Shih Tzus stay chocolate-colored.

Even if your puppy is genetically liver (bb), there’s no guarantee that rich color will last into adulthood. That’s because coat color fading is influenced by other genes that are not yet fully mapped or testable. This is where things move from science to mystery.

Is there a test to know if a Shih Tzu will fade?

Not yet.

While you can test for liver, black, and cream base colors using known genes (like TYRP1, E locus, and K locus), you cannot test for fading. That’s because fading is considered a polygenic trait, meaning it’s likely controlled by a combination of many small genes, and we haven’t identified them yet.

Even companies who test for these traits like Embark note this in their documentation: “We do not test for genes responsible for fading or changes in coat intensity over time.” They acknowledge that coat fading is unpredictable and outside the scope of their genetic reporting.

So if you’ve ever asked a breeder, “Will this puppy stay dark?”… and they hesitated… it’s not because they’re unsure of their breeding quality. It’s because science literally doesn’t exist yet to answer that definitively.

So How Do Ethical Breeders Prioritize What Matters Most?

Here’s where experience and intention make all the difference.

At Divine Pups, we know that a Shih Tzu’s coat may change, but their temperament is what truly shapes their quality of life (and yours). While many buyers get caught up in color or markings, ethical breeders are focused on something far more important: who your puppy is on the inside.

Temperament is what determines if your puppy will be confident, social, gentle with kids, or calm in new environments. It’s what makes them fit seamlessly into therapy work, service placements, or simply family life.

That’s why ethical breeders:

• Use intentional curriculum starting at birth to nurture secure, adaptable temperaments

• Perform temperament evaluations before assigning puppies to homes

• Match based on personality traits, not first-come-first-serve or just appearance

• Prioritize mental soundness over trendy looks or rare colors

Color might catch your eye, but temperament is what stays.

Why does coat fading happen?

While we don’t know exactly which genes cause fading, we do know it’s often seen in liver-colored dogs as well as blacks and some golds. Environmental factors like sun exposure, nutrition, and hormones (especially around spay/neuter timing) can also impact coat color, but genetics is still the strongest factor.

Sometimes, the fading is subtle,like a dark chocolate puppy softening to a medium brown. Other times, it’s dramatic, with deep liver coats lightening to sandy beige by age two.

Either way, it’s completely natural and not a sign of illness or poor care.

So what should new owners know?

If you’re shopping for a liver Shih Tzu puppy and hoping for that dark chocolate look, here’s what you should keep in mind:

• Ask about the parents’ temperament and adult appearance. While color can be helpful to know, what matters most is how your puppy is being raised and the temperament of their lineage.

• Beware of “non-fading” marketing claims. Coat fading isn’t something that can be tested or guaranteed. Ethical breeders prioritize health, structure, and temperament, not just coat color.

• Be realistic. Even with strong, non-fading lines, every puppy is unique.

• Remember: beauty runs deeper than color. Fading doesn’t change your puppy’s temperament, health, or the bond you’ll share.

At Divine Pups, we’re upfront about fading because we believe in preparing you, not just selling you a pretty face. Our liver pups are bred with care, using health-tested parents, and placed in homes that value the whole dog, not just the color.

Final Thoughts

Color may be what catches your eye, but it’s not what builds a lifelong bond. Whether your puppy stays chocolate-rich or lightens over time, the real magic is in their heart, and the way they fit into yours.

And even though you may have your heart set on a liver-colored Shih Tzu, it’s important to remember that what matters most is finding a puppy whose temperament matches your lifestyle. Ethical breeders will always prioritize that above coat color or physical traits, and they’ll keep that at the forefront of every conversation.

So if you’re dreaming of a liver Shih Tzu, choose your breeder wisely. Ask the questions that matter. And be open to the journey of watching your pup grow, change, and become even more lovable with every passing day.

Because at the end of the day, it’s not just about how they look, it’s about how they love. Make sure  you take a peek at our nursery for our Ready Pups!