I have attached four types of crucial evidence to prove, beyond a reasonable doubt, that much of Iranians have indeed maintained their intergral composition.

1. Cavalli-Sfrora - Biological relatedness of 42 populations. "History and Geography of Human Genes 1996"

http://www.geocities.com/truthonrace/MapGene.jpg

2.

Diogo Meyer - "Analysis of Classical and DNA markers of human populations" 1997

http://www.geocities.com/truthonrace/tree.bmp

3.

Cray's Cephalic (Skull) analysis

http://www.geocities.com/truthonrace/MapSkull.jpg

4. Quintani-Murci, Population Movement in Southwest Asia (depicts Aryans (Iranians) moving into Europe, Egypt, Lebanon, India - where soon after, civilization begun) and Kurgan Migration
- the Kurgans were biologically 75% pre-Iranian people as modern mtDNA and Y-chromosome confirm.

http://www.journals.uchicago.edu/AJHG/journal/issues/v68n2/002418/002418.html