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Laundry rooms should, of course, be located for the shortest, straightest dryer exhaust path ... ideally on an exterior wall of the structure. Installation instructions for each dryer brand/model state the maximum distance that allows proper functioning of the machine. Every 90° turn cuts considerably into the allowable length of the ducting. Fire hazard from lint accumulation isn't the only consideration. Drying time, machine performance, and energy usage also comes into play. Long runs passing through unheated attics or crawl spaces often cause moisture condensation inside the duct which results in lint accumulation, eventually leading to a complete obstruction. [Electric] Dryer service life can be shortened when reduced airflow causes the heating element to run at higher-than-intended temperatures.

My laundry closet is also on on interior wall, in my upstairs hallway. The machines face the rear of the house, and the shortest run would have the dryer vent exit the front of the house. I didn't want a vent hanging off the front of my house! Instead we ran the vent down into the floor and through the joists to the back of the house, where it exits via a standard exterior wall vent. The rare time it needs cleaning (every few years?) you need a ladder to access it, but it is easier than climbing onto the roof.

Most dryers recommend no more than 15 feet with one 90 degree. It is best to have the dryer vent through a wall. Long runs reduce the efficiency of the dryer and they need to be cleaned regularly. If you plan an intallation like this, then also plan to regularly clean the vent. That means obtain a cleaning tool that will reach the whole distance of the vent. Try not to go through unheated spaces, and keep the run straight avoiding turns.

Here is a link that might be useful: Dryer Vent Cleaning to Improve Dryer Efficiency

My dryer exhaust is on front of the house, although hidden from direct view behind some bushes. I didn't design it that way, the house was already built when I bought it. Even so, I would chose dryer efficiency over house aesthetics.

Note that some dryers (i.e. high-end GE units) allow for much longer ducting runs than typical. And there is also the ventless condensation dryer option. I would avoid either though (especially the latter) if possible and just find a way to get the dryer near a outer wall.

Can any dryers be vented through the roof?

I had to use 6 inch furnace vent with adapters to vent my dryer because of the long vent length. One Hotpoint dryer I had would not tolerate an 8 foot rise from the basement.