1)Her real name is Antonia - not Sonia. (I think Jayalalitha revealed this in a public address during her spat with Sonia Gandhi. I wish I could remember when this happened). Her dad's name is Stefano Maino.
2)She has lied about her place of birth in her bio data submitted to Parliament when she became a MP - allegedly to cover up her family's ties to Nazi-fascist underground networks.
3)She lied about her education when she ran for Rae Bareli's Lok Sabha Elections.
4)The Mainos(again her original family name) minted millions of dollars by smuggling Indian goods/antiques through Air India and Al Italia from New Delhi and Chennai International Airports.
5)The Mainos have connection with terrorists(in Palestine, with LTTE!) and espionage organizations (KGB due to her dad's background)
Note that if either 2) or 3) is true, she can be prevented from holding office. 4) is despicable 5) is alarming.
I am going to do some more research on this as I am horrified by these claims. If you have any info/links to articles about this topic, please comment/share it with me.