How is it possible for someone to have a narrow upper palate yet a wide lower palate?

[mewcel420]

Title basically. I have this. My upper palate is quite narrow with mild crowding, the lower palate isn't ideally wide but it is fairly wide without tooth crowding. I never see people with a jaw like this and I would like to know how it forms.

 

[Libyan slayer 🐬]

Title basically. I have this. My upper palate is quite narrow with mild crowding, the lower palate isn't ideally wide but it is fairly wide without tooth crowding. I never see people with a jaw like this and I would like to know how it forms.

Genetic is very complicated but never seen someone with this