To expand on my comment, as per nhahtdh's request:
Because clan specific jutsu have to be taught, even though you may have an affinity toward them or less difficulty in learning them.
Unlike Kekkei Genkai, which are techniques (usually) unique to a clan passed down genetically, clan specific jutsu - or Hiden - are passed down through teaching/orally.
Examples of Kekkei Genkai include, but are not limited to, the Sharingan, the Byakugan, the Shikotsumyaku (Kimimaro's bone ability), Ice Release techniques (used by Haku) and Wood Release techniques.
Examples of Hiden include, but are not limited to, the Nara clan's Shadow techniques, the Aburame clan's Insect techniques, the Hyuuga clan's fighting style (Gentle Fist) and the Uzumaki clan's Sealing techniques.
However, it is also noteworthy to point out that Naruto possesses many of the general "abilities" of the Uzumaki clan, such as an incredibly strong life force, great recuperative powers and over the average longevity. He possesses these because, not unlike Kekkei Genkai, they are passed down genetically.
On the other hand, he does not posess the clan's specific jutsu, due to the simple fact that there was no Uzumaki around to teach them to him.