Amazon Route 53 uses the following to PROVIDE high availability and low latency:

• Globally Distributed Servers - Amazon is a global service and consequently has DNS Servers globally. Any customer creating a query from any PART of the world GETS to reach a DNS Server local to them that provides low latency.
• Dependency - Route 53 provides a high level of dependability required by critical applications.
• Optimal Locations - Route 53 serves the requests from the nearest DATA center to the client sending the request. AWS has data-centers across the world. The data can be cached on different data-centers located in different regions of the world depending on the requirements and the configuration chosen. Route 53 enables any server in any data-center which has the required data to respond. This way, it enables the nearest server to serve the client request, thus reducing the time taken to serve.

As can be seen in the above image, the requests coming from a user in India are served from the Singapore Server, while the requests coming from a user in the US are routed to Oregon region.