Yes, your parents can give you the amount as gift towards purchase of your home.
Gift is not taxable to the recipient.
For the giver of the gift-
Normally a person can give up to the annual exclusion amount $13,000 in 2009 ($12000 for 2008) to a person, every year (($26,000 in 2009)$ 24000 in 2008 if spouses joins in for the gift) without facing any gift taxes and note that such amounts do not count as part of your $1,000,000 lifetime total.
Further, IRS allows a person to give up to $1,000,000 in gifts, total, in their lifetime, before they start owing the gift tax. (This gift is not per (donee)person but its a per donor limit). So you can make gifts that are worth up to a million bucks during your lifetime without paying the gift tax. . Even if you do not owe a gift tax because you have not reached the $1,000,000 limit, you are still required to file gift tax return if you made a gift that does not qualify as excludable.
Hence, if your parents have not used up their life time exclusion, they can gift the amount to you without owing any gift tax. They will however, have to file a gift tax return and report the gift to the IRS.
Let me know if you have any question.
Please note: This advice is provided with the understanding that all the relevant facts have been provided by you. Any change in facts might affect the advice given and hence may not be relied on in such cases. Nothing contained in this reply was intended or written to be used, can be used by any taxpayer, or may be relied upon or used by any taxpayer for the purposes of avoiding penalties that may be imposed on the taxpayer under the Internal Revenue Code of 1986, as amended.
IRS can charge a minimum penalty of $100 for not filing the gift tax return timely. There is no underpayment penalty due since there is no tax liability(due to the lifetime exclusion).
In any case, it is advisable to file the gift tax return to be safe.
Particularly things get complicated when parents are deceased and the estate determines that gift were given but no gift tax return was filed to report the gift.