(Note: explicit sexual content)

BELLEFONTE, Pennsylvania (Reuters) - The defense in the Jerry Sandusky child sex abuse case could wrap up its case on Wednesday after days of testimony that included the former football coach's wife saying she never saw anything sexual between him and a child.

The high-profile case that rocked Penn State is racing to a close, with the jury of seven women and five men expected to start deliberations by the end of the week.

Sandusky, a former Penn State defensive coordinator, is charged in Centre County Court with 51 counts of abusing 10 boys over a 15-year period, including some at university locker rooms. He faces more than 500 years in prison if convicted on all counts.

Sandusky' wife of 45 years, Dottie, testified on Tuesday that she had never seen anything inappropriate in her husband's behavior with children.

Several of the accusers, known in court papers as Victims 1 to 10, have testified they stayed overnight numerous times in the basement of Sandusky's home, where he would molest them.

But Dottie Sandusky said that children would sleep overnight as guests perhaps only once or twice a month.

Asked by the defense about the men, now aged 18 to 28, who are accusing her husband, Dottie Sandusky described most of them as pleasant boys when she knew them.

But she described Victim 4, who led off prosecution testimony, as "very demanding ... he didn't listen a lot."

She also denied testimony by Victim 4 of an alleged sexual encounter with Sandusky while on a trip to the 1999 Alamo Bowl in Texas.

Testimony on Tuesday included a psychologist for the defense, Dr. Elliot Atkins, who said Sandusky suffered from histrionic personality disorder. The condition is characterized by emotionalism and attention-seeking, with inappropriate displays of sexual affection, he said.

But a psychiatrist for the prosecution, Dr. John O'Brien, disputed the finding. He said Sandusky was too high-functioning to have the disorder.

The Sandusky case has focused renewed attention on the issue of child sexual abuse and prompted the firing in November of Penn State President Graham Spanier and legendary head football coach Joe Paterno. Paterno died of lung cancer in January.

The prosecution presented witnesses last week who gave often-graphic accounts of abuse ranging from groping and bearhugs in Penn State showers to anal and oral sex.

It was unclear whether Sandusky would testify as the trial entered its final stages.

Judge John Cleland has told jurors he expects the defense to conclude around midday on Wednesday, followed by a prosecution rebuttal. The two sides will give closing arguments on Thursday.

The jury will be sequestered during its deliberations.

(Editing by Lisa Shumaker)