A head-on collision yesterday between a passenger train and a locomotive killed five people and injured seven others, two of them seriously, the national rail company said.

The pre-dawn crash occurred near Lousa, about 120 miles north of Lisbon, said Carlos Madeira, spokesman for rail company Caminhos de Ferro Portugueses.

Four people died at the scene and another died en route to the hospital, news reports said.

The passenger train slammed into the locomotive, which was being used to instruct new operators. The cause of the accident was not known.

The risk of birth defects in children born to couples who are first or second cousins isn't as high as many experts had believed, according to a study that sheds new light on a practice that is stigmatized in many Western cultures.

The study released Wednesday says married cousins are still more likely than unrelated couples to have children with a birth defect, significant mental retardation or serious genetic disease.

An unrelated couple has about a 3 to 4 percent risk of having a child with such problems. But for close cousins who are married, that risk jumps only 1.7 percent to 2.8 percent, the study said.

Researcher Robin Bennett said that is lower than many people, including family doctors, believed to be the case.

"The common-sense point of this is that there is a definite risk, but the risk is rather small," said one of the researchers, Dr. Arno G. Motulsky, professor of medicine and genome sciences at the University of Washington.

Marriage of first cousins is illegal in 30 states and is taboo in many Western cultures, but that is not the case in other places, particularly the Middle East, Asia and Africa. In some countries, up to 60 percent of the population is related by blood, and cousin marriages are preferred to unions of unrelated couples.

Bennett said doctors are confronted with new challenges about advising and treating related couples as more immigrants carry on such traditions in the United States.

"There have surely been lots of terminations of pregnancies because of misconceptions about the actual level of risk," she said.

A New Zealand man who was rescued after falling about 75 feet into the Grand Canyon was listed in fair condition yesterday at a Flagstaff hospital.

Richard Cole, 29, was walking along the canyon's west rim, about a quarter-mile west of Hopi Point, when he slipped and fell Wednesday, authorities said.

Cole's brother witnessed the fall and flagged down a shuttle bus to report the accident and alert authorities.

Cole had an open ankle fracture and was taken by helicopter to Flagstaff Medical Center, where he remained yesterday.

Canyon officials said Cole's rescue was the third successful rescue operation in the last month.