A Texas woman has accused a longtime Colorado fertility doctor of using his own sperm -- rather than sperm from an anonymous donor -- to impregnate her mother nearly four decades ago.

Maia Emmons-Boring told KUSA-TV that she and her sister have at least five previously unknown half-siblings fathered by Dr. Paul Brennan Jones. The sisters also claim that they have been contacted by three more people linked to the women through DNA sites like Ancestry.com and 23andMe.com.

"I don’t deny it. I don’t admit it,” Jones, now 80, told KUSA. When a reporter asked Jones if he fathered the children, the doctor called the question "impertinent" and added, "I'm not going to answer it."

“I feel [Jones] needs to own up to what he did,” Emmons-Boring told the station at her home in San Antonio. “I would like to ask him, ‘Why? Why did you do this?’”

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Emmons-Boring, 39, says she realized that the father she’d grown up with was not her biological father after receiving a message from a stranger in her Ancestry.com inbox on New Year's Eve of last year.

“It looks like we’re close matches, so I’m assuming we’re half-siblings,” wrote the stranger. “My father was a sperm donor in Grand Junction, Colorado [Emmons-Boring's hometown]. I’ve found three more half-sisters and a half-brother who’s [sic] parents also used the donor at the same clinic.”

At first, Emmons-Boring thought the message was part of a scam and began researching the reliability of Ancestry’s DNA testing. What she found online convinced her the message was not a hoax, and after informing her younger sister, Tahnee Scott, the pair decided to talk to their mother, Cheryl Emmons.

“At first [our mom] said, ‘No,’ and then my dad, who is very quiet and reserved, he says — he kind of interrupted her — he said, ‘Yes, we used a sperm donor to conceive you and Tahnee,’” Emmons-Boring said. “Our world got turned upside down more or less,” Scott added.

The station reported that Cheryl Emmons consulted Dr. Jones to help her conceive out of fear that she and her husband would be unable to do so due to his recent bout with testicular cancer.

Jones, who had been practicing since 1972, assured Emmons he would use an anonymous sperm donor.

"[Jones] said there were medical students, you know, at St. Mary’s [Medical Center], and so, anyway, one thing led to another and we said, ‘OK,’” Emmons told KUSA. At the time, freezing sperm was not common practice, so doctors relied on “fresh samples” provided 30 minutes or so before the mother’s visit.

“Instead of using ‘fresh’ sperm from an anonymous donor to inseminate Mrs. Emmons during these procedures, Dr. Jones used his own ‘fresh’ sperm to artificially inseminate Plaintiff Mrs. Emmons,” the suit alleged.

Jones procured successful insemination and helped deliver baby Maia in 1980. Five years later, Jones assisted again with the artificial insemination of Emmons and returned to helped deliver baby Tahnee.

“We have pictures. Maia has them now,” recalled Emmons. “[Jones] took some pictures of all of us, you know, in the delivery room.”

Emmons recalled that when she visited Jones’ office in Grand Junction, “He never included my husband in anything, and I thought that was odd.” However, Emmons added that “I really thought he was doing a good thing for me and my sweet husband.”

According to the lawsuit, Jones told the couple to go home on the night of the insemination and "make love so that they would not know if the conceived child was from the anonymous donor...” Emmons said she had thought it was possible, though unlikely, that her husband was the biological father of her daughters.

In the years that followed, Jones would occasionally send letters to the family. After the Emmons family moved to California, Emmons said they unexpectedly ran into Jones at a mall and he made a point of saying hello to Maia.

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Emmons-Boring told KUSA she set out to find who her biological father was after her sister took a DNA test and confirmed that they had been conceived from the same sperm donor. She was it took her three weeks to figure it out.

Her attorney requested a genealogy report, which used a public family tree posted by Dr. Jones’ brother. The tree linked a common ancestor, a second cousin, between Emmons-Boring and Jones. From this, genealogist Kathleen Hinckley deduced that the siblings might be the biological children of Jones or his brother.

Jones’ brother said he couldn’t have supplied the sperm because he moved from Grand Junction in 1972.

When KUSA confronted Jones at his Grand Junction home, he told the station: “My attorney says don’t talk to the press.” He said he would not take a DNA test, “because I don’t want to have any incriminating evidence against me.” He later added that he might consider taking a test if the Emmons family would consider dropping the case.

“Never, ever did [Jones] tell me that he would be the donor,” said Patty Gray, a patient of Jones whose son Ryan appears to be a half-sibling of Emmons-Boring and Scott. “I would have remembered, because I would have left.”

“Here is a doctor who is supposed to be a professional, somebody you have trust in,” she added. “He owes all of us an explanation.”

“If we would have stayed in Grand Junction, we could have been marrying our brothers and sisters, which is kind of disgusting to me,” said Shawna Hults, who was donor-conceived and is thought to be another half-sibling.

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The lawsuit alleges negligence, fraud and other causes of action and seeks damages in civil court.

Currently, Colorado has no specific law against doctors using their own sperm when inseminating a woman from an “anonymous” donor. Texas, where Emmons-Boring currently lives, passed a law earlier this year prohibiting a doctor from inseminating a woman with his own sperm without her consent.

Emmons-Boring told KUSA she plans on working with Colorado legislators to help change the law there, which could open up the possibility of doctors being charged with sexual assault.

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