There is at least one other case, reported in 2006, of a high rate of autism and related disorders among children with a common sperm donor—four of the seven known children of California Cryobank donor 3066. Other accounts of shared medical problems among donor children have cropped up. Mundy writes of a group of mothers on the DSR who used Donor 1476 of the Fairfax Cryobank in Virginia, and discovered that while he had claimed to be allergy-free, several of the more than 35 children he produced have problems with asthma. And in Michigan, pediatric hematologist and oncologist Laurence Boxer, MD, diagnosed five children born into four different families with the same genetic disease, severe congenital neutropenia, a blood abnormality that highly increases vulnerability to bacterial infections and raises the risk for leukemia. In treating the children, Boxer discovered that all of their parents had used the same sperm donor, from a Michigan sperm bank. The rate of severe congenital neutropenia is one in five million children in the general population, but a genetic carrier has a 50 percent chance of passing it on. Boxer, writing in the Journal of Pediatrics, surmises that the donor's malfunctioning gene only showed up in his sperm—a condition known as a gonadal mosaicism—and without genetic testing, he would have seemed perfectly healthy.

The sperm banks have taken hits as a result of these cases. Some parents say they have phoned in their concerns, describing their children's problems and asking if any similar accounts had been filed, only to learn later that the banks kept no record of their calls and continued to sell the donor's sperm. That has not been the experience of the Donor X group. When Dylan got his diagnosis, Gwenyth called California Cryobank and had a long talk with a genetic counselor, Mindy Bukrinsky, who worked there at the time. "She asked a lot of questions. I felt they took it seriously," Gwenyth says. Theresa, Elizabeth, and Victoria followed up with calls of their own. Persuaded that this donor posed a higher-than-average genetic risk, the bank pulled his sperm from general circulation. Cryobank also notified families that had vials in storage about the autism—and contacted the donor himself. "We wanted him to know for his own future reproduction," says Bukrinsky.

The bank's handling of this particular case seems fairly unassailable. But that doesn't mean the same is true across the industry. In the United States, sperm banks are virtually unregulated. As a result, they function much as adoption agencies did a half-century ago: Secrecy is the norm—the concern more about protecting the donors' anonymity than helping families solve health problems that develop as their children grow. California Cryobank facilitates the updating of a donor's medical history over the years for the benefit of its clients. But as the DSR's Wendy Kramer points out, this is rare. In most cases, the purchase of sperm is a one-time transaction.

Sometimes the banks go to seemingly unreasonable lengths for the sake of a donor's privacy. In 1991 Diane and Ron Johnson wanted to have a second child. So they went back to the California Cryobank for more vials of sperm from Donor 276, with which they'd already conceived a daughter, Brittany, in 1989. The second time around, the bank told the Johnsons that Donor 276 had a family history replete with kidney disease—his mother and aunt both suffered from it. The bank had evidence of this ever since the donor filled out a profile chart in 1986. Brittany became sick with the illness (autosomal dominant polycystic kidney disease) four years later, at the age of 6. The Johnsons sued the bank for initially failing to disclose the information, and to compel Donor 276 to testify about it. They argued that he had information that was crucial to future decisions about their daughter's treatment.