I file married and jointly and do not itemize. I saw that the amount in line 40 of my 1040 form shows 15,100.00 instead of 12,600.00. I didn't do it, but its wrong.

If you and your spouse are 65 or older, then your standard deduction is higher.

2016 Standard Deductions

Single    $6300  (65 or older + $1550)

Married Filing Separately   $6300  (65 or older +  $1250)

Married Filing Jointly           $12,600  (65 or older + $1250@)

Head of Household $9300  (65 or older + $1550)

TurboTax calculates the standard deduction for you based on the date of birth you entered in Personal Info.

So $15,100 is correct if you have TWO of the following:
-- You are age 65 or older.
-- Your spouse is age 65 or older.
-- You are blind.
-- Your spouse is blind.

If that is not correct, yes, you should amend to correct your birthdate and/or indication you are blind.
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Standard Deduction  Joint = 12,600 + 1,250 + 1,250 = 15,100