"You and your neighbor, whatever your appearance, only differ in 0.1% of our genome." Lluis Montoliu, a geneticist, says that there are 3 million letters which fortunately make us all different. Although it is a small amount of DNA, it contains a large number of chemical letters. The Spanish scientist believes we shouldn't talk about a reference genome of humans for the entire world. The researcher at the National Center for Biotechnology, CSIC (CNB) says that reference genomes would need to be discussed in plural.
It was believed that once the DNA sequence of our genome had been read, it would make it relatively simple to solve many problems. The genome is much more complex than that. This has been proven by experience. The genome is a guidebook that allows you to activate and deactivate genes as a result of environmental factors, diet and age, and internal compensations within your genome.
For example, a common genetic variation in Spain might be innocuous but can be dangerous in the British Isles. Montoliu explains that the genome functions as a whole. This means that any variation caused by any factor could have been counterbalanced in another part of the genome that neutralizes it harmful effects. It's clear why there cannot be one reference genome for the entire planet.