Zaheer Khan doesn’t think Indians can bowl fast ‘naturally’:
“It’s not a natural thing,” Zaheer told Times of India. “Indian bodies are not designed to bowl fast but that said, it’s not very different from bowling outside India. Basically you have to spend a lot of time understanding yourself, your art, and then find out what works for you and what doesn’t. It also involves a lot of hard work.”
If I were charitable, I would interpret Khan as saying that fast bowling itself isn’t natural; it’s a fine art that can only be perfected through practice. Anyone who has seen a slow-mo replay of a fast bowler’s action understands the enormous strains involved. See, also, “Broken backs, fast bowlers.”
But if I were simply reading the text, I’d conclude Khan thinks there’s something wrong with the Indian gene pool. The problem with this argument is that it’s based — or related to — a post-colonial pathology: many South Asians (particularly right-wing Hindus) believe that Indian men aren’t masculine enough, and the British took advantage of their femininity.
On the other hand, there may be reasonable nature-nurture arguments to explain India’s lack of fast bowling talent. For example, experts looking at Kenyan runners — a group that routinely dominates international competitions — have argued that high elevation, a culture that relies on running and walking, and possible genetic advantages all conspired to produce lethal running machines. Is there any reason to believe Indians are susceptible to cultural/genetic factors, or maybe other incentives, that drives talent away from bowling fast? Ideas anyone?
Ducking Beamers: A Cricket Blog 
well thankfully Indians have nice batting genes.
Maybe there isn’t enough motivation for a player to risk his body to an extent that he could injure himself and be stuck in first-class cricket for his whole career, not making enough money.
Historically, India has produced very few genuine fast bowlers.
It doesn’t make much sense. Look at Pakistan, Bangladesh and Sri Lanka. They have produced good fast bowlers. Was there no mixing of the gene pool between people in India and those countries?
There are better reasons. The pitches that favor batting. The weather in some parts of the country. Lower per capita GDP at least when compared to Pakistan & Sri Lanka for most of the previous decades.
I second what Krishna has said.
Indian bowlers concentrate much on his line and Length, Coach of Indian Cricket team thinks that Fast Bowler is not the key for Win, though Line and length makes bowler perfect, Example : Parveen Kumar, his inswing is far better than others