It had all the makings of a headline news story. A hacker had supposedly broken into the grading system for an MIT biology class and changed the grades of 22 students.

The announcement ran in yesterday's Boston Globe and came on the heels of what some newspapers have called the biggest scandal in Ivy League history after 78 Dartmouth College students were accused of cheating in an introductory computer science class last week.

But yesterday afternoon, officials at MIT said the allegations simply were not true.

The grade-changing incident was actually just an inadvertent error made by a person authorized to enter grades, according to a statement by Professor Harvey Lodish in a press release from the MIT News Office.

"The sorting of a grades spreadsheet is done by using a computer mouse to highlight the two columns of names and corresponding grades," the press release reported.

"In this case, there was a slip-up in the use of the mouse and only the column of names was sorted, resulting in grades being assigned to the wrong people. The error raised the grades of two students and lowered the grades of 20 students," it said.

As whispers about inadequate computer security and moral lapses quieted down yesterday, MIT students said they were not disturbed by the incident.

Scott D. Johnston, an MIT sophomore, said he retained faith in his fellow students.