dragonborn

As a race, dragonborn is described in Races of the Dragon and also noted in other supplements.

4e PHB Readthrough – Chapters 1-3 « Geek Related 2008

We start off with the dragonborn, the whole-cloth new race in 4e (the tiefling is new as a core race but was there in 3e).

4e PHB Readthrough – Chapters 1-3 « Geek Related 2008

Although, dragonborn and tiefling were both eminent in 3e.

4e PHB Readthrough – Chapters 1-3 « Geek Related 2008

Its not to hard to look at the back of the MM to get your classic races though, and noone says you have to let eladrin and dragonborn in your temple of elemental evil …

D&D 4e’s Out… And It’s Awful. Here’s Why « Geek Related 2008

And good point on the minor action dragonborn breath thing.

4e PHB Readthrough – Chapters 1-3 « Geek Related 2008

Dumping half-orc and gnome for tiefling and dragonborn

4e Compilation PDF « Geek Related 2008

However, there are concerns that WotC will attempt to shoe-horn 4E's new races (the dragonborn and eladrin) and the basic classes (including the bard and paladin) into the setting where there is really no place for them.

Archive 2009-11-01 Adam Whitehead 2009

However, there are concerns that WotC will attempt to shoe-horn 4E's new races (the dragonborn and eladrin) and the basic classes (including the bard and paladin) into the setting where there is really no place for them.

The Worlds of D&D: Dark Sun Adam Whitehead 2009

The book also talks about Arkhosia, the last dragonborn empire.

D / RPG News Crothian 2010

Another player will likely be a ranger, and another likely some sort of dragonborn defender-class.

D / RPG News Andrew D. Gable 2010