Welcome to Gaia! ::

I was having a conversation about something with one of my friends that lead to a very long argument
the technique Izanagi....I say like it says in chapter 510-511 requires both senju and uchiha DNA however...my friend says it ONLY requires a sharingan the senju DNA just amplifies the power and prolongs the jutsu
I would like input if you guys are willing

I have seen this one yes...though the wording is not complete and leaves some open to interpolation
"To make full use of Izanagi users must also have the genetic traits of the Senju, who are also descended from the Sage.[3]"
to make full use...not required...though the manga in chapter 511 clearly states
ONLY those who have the powers of both uchiha and senjuu can access Izanagi

Izanagi, named for a god who helped spawn many islands and deities, is a Genjutsu technique which was declared a Kinjutsu by the Uchiha Clan. Using Izanagi grants the user the ability to turn wounds and disadvantages into nothing more than dream. It also makes attacks and advantageous maneuvers real, thus giving one complete control over their own reality through an illusion cast on themselves. The creative power of Izanagi was first used the Rikudou Sennin. Izanagi uses the mind and spiritual power of Yin to shape reality, and the vitality and physical power of Yang to give it life. The Rikudou used that same power to create the Bijuu from the Juubi. The Rikudou's powers were passed on to the Uchiha and Senju, and only one containing both of their power can use the jutsu.

When jutsu is cast on one's own self, any damage received while it is active is negated. Their crippled form will shudder away like an illusion into nothingness while they appear unharmed away from the danger. For those who do not possess the Rinnegan, using the jutsu has a drawback, as using the jutsu will cause their vision to be lost forever. This result caused the Uchiha to declare it forbidden.

The jutsu normally has a short time limit which varies from Uchiha clan member to clan member. This was extended through the experimentation of Orochimaru, which granted almost a minute of immortality for each eye sacrificed. This was used to full effect when ANBU Root leader Danzou had a portion of Senju Hashirama and numerous viable Sharingans implanted in his right arm. This extended time was active at the cost of an ongoing drain on Danzou's chakra. So when active, it allowed him to absorb numerous fatal attacks at the cost of one of the Sharingan eyes permanently closing on his arm and becoming useless. Should Danzou need to conserve chakra and protect the eyes, he would cancel the jutsu and attempt to avoid critical hits.

Leafninja.com description

You can post any link on gaia to my knowledge and honestly even if it were against gaia tos someone would have to message a mod and thats not gonna happen.

As for the tech, I think it can be done without the senju dna, but at teh same time the earlier uchiha (such as in mandara's time) still had much closer blood ties to the Senju since they are from the same ancestor it goes to reason that they do have a small amount of what makes the senju unique in them, as well as the senju having a small bit of the uchiha power, though again it would be in the older days not current timeline as blood dilutes over long periods. (unless there is some mass incest)