Let's learn about the Opaline Mutation now!
Firstly, in budgies, the chromosomes of the sexes are opposite to the chromosomes in humans. Thus -
Males = XX
and Females = XY
Secondly,
What is a sex linked mutation?
- A sex linked mutation is a mutation that is only carried in the 'x' chromosome.
Now let's start on the actual learning -
PHENOTYPE :
The Opaline Mutation is a mutation present in budgies that make the following changes occur in their phenotype which is their physical appearance -
a) It makes the barrings on their head and shoulders lessen or disappear entirely.
For example, here are two of my budgies -
As you can see in the above picture, the budgie has a lot of black stripes on it's head and on it's shoulders.
But in this picture, you can easily see how much reduced the black stripings are in the head and shoulders! (sunsilk is better just saying)
b) It changes their wing colors.
A regular budgie will have black and their base color colored wings (like black/yellow for a green birb and black/white for a blue birb)
But the opaline gene changes that. Instead it changes the wings from 'Black and base color' to 'Black and body color' (like black/blue for a blue birb and black/green for a green birb)
For example, here are two of my budgies again -
You can see in the above picture that the bird has black striped with white wings (white being the base color of the budgie)
But this bird has black and blue (blue being his body color) wings!
That's the physical changes the opaline gene makes, everything else of this budgie is normal.
GENETICS :
The opaline gene is a sex linked recessive mutation meaning it can only be carried in the 'x' chromosome.
That results in a budgie male to be -
1. Opaline : Having two 'x' chromosomes carrying the opaline gene as it is recessive to the wild type
2. Not opaline : Having none of the 'x' chromosomes carry the gene
3. Carrier : Have one of the 'x' chromosomes to carry the gene, but the appearance of that budgie will be of the wild type as Opaline is a recessive mutation
That also results in females being -
1. Opaline : Have her single 'x' chromosome carry the opaline gene
2. Not opaline : As she doesn't carry two 'x' chromosomes, her appearance tells it all. Either an opaline or not an opaline.
Let's have some fun with the punnet square now! (pretend the red color 'x' carries the opaline gene and the black 'x' doesn't)
a) Two opaline birds produce
= 100% opaline babies
b) Opaline male and Normal female produce
= 100% male babies will be carriers and 100% female babies will be opaline
c) Normal male and Opaline female produce
= 100% male babies will be carriers and 100% females will be normal
d) Carrier for opaline gene male and normal female produce
= 50% of male babies will be carriers, 50% of male babies will be normal, 50% of the female babies will be opaline and 50% of the female babies will be normal
e) Carrier for opaline gene male and opaline female produce
= 50% of the male babies will be opaline, 50% of the male babies will be carriers, 50% of the female babies will be opaline and 50% of the female babies will be normal
And THAT sums up the opaline mutation!
