Officials in Texas just finished collecting cheek-swab samples from the 437 children and alleged parents in order to determine who is related to whom.
The children were removed from a polygamous commune in Eldorado earlier this month during a raid sparked by reports of sexual abuse of underage girls. According to news accounts of the Fundamentalist Church of Jesus Christ of Latter Day Saints (FLDS) in Eldorado, pubescent girls were forced into "spiritual marriages" to older men.
The cheek-tissue samples will be analyzed for DNA, the tightly coiled threads of deoxyribonucleic acid found inside each of the trillions of cells in our bodies.
Results could have legal implications, including any evidence for possible statutory rape, which includes individuals below a certain age deemed legally incapable of consenting to sexual activity. In Texas, 17 is the minimum age, making it illegal for anyone under the age of 17 to engage in sexual activity with another who is at least three years their elder. (An individual must be at least 16 years old to enter into a legal marriage in Texas.)
"Now not only can we look at alleged relationships between parents and their children," said Robert Allen, a professor of biochemistry at Oklahoma State University, "but now we can look at alleged sibships (siblings), alleged half-sibships (half brothers and sisters)."
To find a male child's father, researchers will look for match-ups in DNA markers found on the Y sex chromosome, which is passed down from fathers to their sons.
"All males descended from a common male and female ancestor would have exactly the same Y chromosome passed unchanged from generation to generation," said Allen, who is also director of the Human Identity Testing Laboratory. "So I will have the same Y chromosome as my brother, father, son, paternal uncle, paternal cousin."
Mothers can be linked to children with DNA found in the cells' energy-producing structures called mitochondria. The mitochondria hold a separate set of genes passed down from mothers to their offspring. Based on the age of the child, officials could then figure out how old the mother was at the time of conception and the age of the father.
The information will be news only to officials, as the mothers and children within this Mormon sect know who's who. "It's not a free-love community. These children are being raised by their mothers. It's the father who may be having multiple wives. All these children know who their father is and who their mother is," said Stuart Wright, a professor of sociology at Lamar University in Texas. "The question is whether some of these women were under legal age when they were either married or impregnated. I think that's what the DNA tests are probably going to try to show."
The DNA testing could also provide incest clues.
Though no evidence of incest has been reported in the current case, the Texas Department of Public Safety (DPS) is conducting the criminal investigation of possible sexual abuse at the Eldorado compound, also called the Yearning for Zion (YFZ) ranch.
"We assisted Child Protective Services in serving a search warrant at the YFZ ranch. While we were there, we observed activity that led us to believe that there may be some crimes that were occurring," said Tela Mange, a spokeswoman for the Texas Department of Public Safety. "We obtained a second search warrant. And we are in the process of conducting a criminal investigation."
The investigation does include looking into possible "sexual abuse," Mange told LiveScience. "We haven't been more specific than that at this point."
However, incidents of statutory rape and incest have surfaced in other investigations of members of this sect. The sect's "prophet" Warren Jeffs was convicted in Utah last year of being an accomplice to rape, for arranging a marriage between a 14-year-old girl and her first cousin; in Arizona, Jeffs faces trial on eight charges of sexual conduct with a minor, incest and conspiracy, according to news accounts.
Jeffs is now being held in the Mohave County Jail in Kingman, Arizona, where he will be tried on charges of being an accomplice to incest and sex with minors.
"In incest, for example, you can determine whether or not a man is the father of the mother just by doing the standard parentage analysis." Allen said. "Then you can determine if the man is also the father of her child." A strong positive test would suggest the man mated with his own daughter, Allen added.
Incest is a statutory crime, and is defined as sexual intercourse between close blood-relatives. The prohibited degrees of incest vary from state to state and can include brothers and sisters, parents and children, aunts or uncles with nephews or nieces, and grandparents and grandchildren.
In Texas, it is illegal for a person to have sexual relations with: a current or former stepchild or stepparent, an uncle or aunt (or half uncle or half aunt), or a brother or sister (or half brother or half sister), according to the Texas Attorney General's office.
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Jeanna served as editor-in-chief of Live Science. Previously, she was an assistant editor at Scholastic's Science World magazine. Jeanna has an English degree from Salisbury University, a master's degree in biogeochemistry and environmental sciences from the University of Maryland, and a graduate science journalism degree from New York University. She has worked as a biologist in Florida, where she monitored wetlands and did field surveys for endangered species. She also received an ocean sciences journalism fellowship from Woods Hole Oceanographic Institution.