Yes, a young boy was forced from school for carrying cystic fibrosis alleles

By Razib Khan | October 18, 2012 9:19 pm

Update II: This comment sums up the pertinent issues.

Update: Please see comments below. This may be an infectious disease story, and not a genetic one.

When a reader sent me an email about the story, I assumed it was a rather sophisticated hoax. The short of it is that an 11 year old boy, Colman Chadam, has been pulled out of his school in Palo Alto because he carries alleles for cystic fibrosis, though he is asymptomatic (i.e., he has never manifested any symptoms of c.f.) administrators are worried that he might pose a risk to some students who do show progression of c.f. (bacterial infections can spread from child to child). As you probably know about 1 out of 30 people of European descent is a carrier for one of the many thousands of mutant variants for cystic fibrosis. The details of Colman Chadam’s results are not totally clear. Is he just a carrier? Or does he have two copies of cystic fibrosis, but somehow they differ enough that they can functionally complement each other?

We don’t know. But we do know that the lawyer from the school, Lenore Silverman, has stated that “The district is not willing to risk a potentially life-threatening illness among kids.” The risk here is non-existent. Not to be creepy, but does the school require that people with various venereal diseases also avoid the premises? With the small, but non-trivial, frequency of sexual abuse at school they too post a illness risk to the kids. In fact, more than Colman Chadam.

You can read everything at The San Francisco Chronicle. Perhaps you want to contact some of the staff at Jordan Middle School in Palo Alto. These people should be ashamed of themselves. I know we live in a litigious society, and being in education isn’t the easiest job, but we deserve better than this!

MORE ABOUT: Genetics
  • Chad

    In Palo Alto…….lol

  • Tim

    After reading the article, wouldn’t he be the one at risk. He doesn’t have the disease, but may have a susceptibility to it. If other students on campus have it, couldn’t they be a risk to him?

  • SC

    Random, but unfortunately there are increasing numbers of reports of similar incidents of genetic discrimination. See for example:

  • Razib Khan

    #2, if individual manifests the disease they may spread bacterial infection to other sufferers. so they’re worried on those public health grounds (there are other CF kids at the school who actually have the disease).

  • biologist

    It sounds like Colman has two potentially pathogenic CFTR alleles, resulting in atypical CF without lung involvement. It also sounds like there are other children with classic CF at Jordan.

    There is apparently a risk of cross infection among children with CF.

    What doesn’t make sense from the article is that it sounds as if there are already >2 children with CF at Jordan including Colman. So why is he being singled out for reassignment?

    I have no idea whether children with atypical CF tend to harbor more pathogenic bacteria than children with normal CFTR alleles.

  • gcochran

    Kids with symptomatic CF, over time ( doused in antibiotics) develop an odd and unpleasant set of microbes in their lungs. Burholderia cepacia, in particular, is a big problem. People with CF typically catch it from other people with CF. CF experts ban people with B. cepacia from CF events and meetings.

    I suspect that this has something to do with the story. There may be misunderstandings: maybe among the educrats, certainly among the reporters. If this kid has B. cepacia, they can’t have him in the same school as other CF kids.

  • Christina

    I’m confused here. CF is a genetic disease, right? How can it be spread from one person to another?

  • Matunos

    #7: Like all genetic conditions: through reproduction.

    But seriously, I think it’s more to do with the bacterial infection stuff everyone above your comment has mentioned.

  • April Brown

    I wonder if they also kick out the children of antivaxxers.

  • Christina

    #8: Right, gcochrane’s comment wasn’t there when I wrote that reply, and the previous comments merely mentioned bacteria, so I was confused about why this boy’s genes would have anything to do with bacterial infections. So, if I understand correctly, B. cepacia cannot establish itself in healthy lungs, but in individuals with CF, the bacteria can colonize their lungs and trigger the disease, and then be spread to other people with those genes?

  • gcochran

    You got it. At this point, we’re likely talking about a CF-adapted strain of B. cepacia. Antibiotic resistant, of course. There was some sort of get-together of CF patients back in the 1980s that had bad consequences. And since then, I think, others. B. cepacia seems to speed up the lung decline generally seen in CF patients.

    If this kid has B. cepacia, he is not unsymptomatic.

  • Paul Ó Duḃṫaiġ

    Interesting we have the highest rate of CF in the world here in Ireland. So I can’t see the educrats here trying to implement a similar policy

    In total about 1 in 19 of the population (5.26%) of population are carriers of relevant alleles. Looking at some stats I see the prevalance of CF in newborns in Ireland is: 1 in every 1,461 live births. By comparison the overall European average is 1 in every 3,500 live births.

    Northern Ireland = 1 in every 1,850 live births
    England = 1 in every 2,500 live births


  • Eurologist

    Educators are pressed between a rock and a hard place. For many situations like this, there are no precedences to rely upon. Unfortunately, too often, school lawyers win out in initial decisions – because the science is too remote and not widely available and understandable, and the schools need to protect themselves from law suites (in the notoriously litigious US). I am sure this will get sorted out, eventually, but what is lacking is the process: in case there is a question, how can the decision-making process be performed and accelerated such that the student in question does not suffer from an undue burden?

  • Dm

    The district isn’t completely in the wrong, but most likely in a vulnerable legal position. It appears that the district has a formal policy of not enrolling a second CF child in a school where one is already enrolled. But it is unclear how it applies to children who are already enrolled (they already got two!), or to biallelics with hypomorphic alleles / alleles of uncertain penetrance (my understanding is that this kid is a biallelic, but only one of the alleles is a known high-risk mutation, but all sources are vague on this important detail)

    If GINA applied, then it would have been illegal to discriminate on the basis of genetic makeup, but this isn’t a workplace.

    What I also find fascinating is that the parents chose to disclose genetic info of their child, apparently w/o any overriding reason to do so. And they have guts to call their line of reasoning “an overabundance of caution“! Some caution, yeah right …. You really gotta be more careful with disclosure of the genetic makeup of the minors who can’t consent!

  • Razib Khan

    #14, You really gotta be more careful with disclosure of the genetic makeup of the minors who can’t consent!

    genes are different (because you can’t change them with current tech). but parents make minors do all sorts of crazy shit.

  • Mell

    Paul (#12)

    Being a carrier of the CF allele (one copy), give the carrier some degree of genetic protection from cholera. So you find higher incidences where the historically, endemic cholera rates were high; ie Ireland.

  • gcochran

    Especially since cholera first arrived in Ireland back when the world was young, in 1832.

  • Douglas Knight

    @5,14: The reason that the school already has more than one CF student is that they are siblings, so there’s no point separating them.

  • Dm

    #18 where did you get this tidbit? There is a quazillion news stories but most of them just repeat the same stuff. Some speculate that the boy is a monoallelic carrier, and others that he’s a biallelic, but I don’t think anyone knows for a fact.

    Another interesting twist is that the school may have claimed that they are transfering this child to protect him rather than those other students with CF, citing a 2003 paper which claimed that asymptomatic CF carriers are also at risk for picking the bacterial infection from CF patients?

    But then, as some readers comment, if a school must protect asymptomatics, then it should administer a compulsory genetic test to all students attending the same school as a CF patient!

    Others claim that the school must have violated HIPAA, but it sounds far fetched. It appears that the public disclosure came from the parents, as they geared to fight the school transfer, rather than from the school itself?

  • Douglas Knight

    I got it by reading the article Razib linked to.

  • John Turner

    #18, #20
    That’s not correct. Besides his brother there are to other siblings with CF at the school, who are at risk of infection. Nothing is mentioned about his sibling’s genetic makeup, so we can probably infer that he doesn’t have the same set of mutations, since he wasn’t asked to leave the school.

    From the article: “A few weeks into the school year at Jordan Middle School, school officials took note of Colman’s medical history, information that eventually was shared with another Jordan parent whose two children have classic cystic fibrosis and are predisposed to chronic lung infections.”

  • Michele

    He is being referred to in other sources as a ‘carrier’ with a single CF-causing mutation, not two. If that is the case, this is the most egregious case of hysterical discrimination since the Ryan White debacle. It seems more likely, though, that somewhere some of the facts are getting mangled in this story.

    Just for reference, the CF carrier rate is 1 in 25 to 30 people. That means there are millions of carriers walking around and we certainly don’t hear of this frightening increased risk of infection impacting literally millions of Americans each year. It seems that the relative risk is being significantly exaggerated. If such a risk truly threatened affected individuals, wouldn’t it be especially unsafe for them to live in homes with two CF carriers, i.e. their parents, where they are sharing food, facilities and air?

  • Paula

    @22, I think the other outlets may be insufficiently informed. the SF Chronicle article is more nuanced, and seems to indicate the boy is biallelic but asymptomatic.

    nowhere have I been able to find a reference to exactly what and how many mutations he has. I did find one that notes his parents have not released that information.

    the SF Chronicle story says, “In the evolving field of cystic fibrosis diagnosis and treatment, there is debate about which variations mean someone has the disease versus being a carrier only.
    Because of Colman’s rare genetic combination, his parents and doctors have closely monitored him to make sure he doesn’t have the disease.
    His physician has documented that he doesn’t, and he never had a clinical diagnosis of the disease, his parents said.”

    why would they continue monitoring if he only has one copy? why would the parents not be trumpeting, “heterozygous, no problem” ?

  • Paul Ó Duḃṫaiġ

    @16 — I’ve always wonder if the high level of CF in Ireland is due to the massive TB epidemic which existed in Ireland until the late 1940’s/early 1950’s. About 6-7% of all yearly deaths during the 1940’s were from TB.

  • Dm

    BTW – just spotted the first (and so far the only one) English-language media mention of a CF blowout in Russia, where a popular radio show about “made-up and dubious medical conditions” poked obscene fun at CF children. Among other things, the radio hosts noted that no celebs ever suffered from CF, so the disease must be a total fake.

    But another tidbit worth noting is the headline of the piece, about Terminally Ill Children. CF is essentially written off as an incurable terminal childhood disease there, and virtually no CF chidren survive into even early adulthood (Late Katia Kostromina, a local CF community organizer hero, had a rare distinction of living till 20)

  • JohnV

    I’m late to the game and apologize for that but to sort of recap the pertinent issues/questions (some of which have been previously mentioned here):

    The medical basis for the concern is that transmission of infections between CF patients is a real thing and results in segregation of Burkholderia cepacia complex (primarily B. cenocepacia and B. multivorans, but there are others) positive and negative individuals. Colonization with Bcc organisms frequently, but not always, marks the worsening of conditions and can lead to rapid death. Bcc infections are a relative recent phenomenon. In the 1970s CF patients didn’t get them, in part because they died from their P. aeruginosa infections earlier in life. While P. aeruginosa infections of CF patients are not typically spread patient to patient (although epidemic strains are turning up now), Bcc infections are spread from patient to patient. (There’s a lot of evolution/microbiology to explain this, I’ll spare you all :P)

    With that in mind, if a school does not feel they can appropriately segregate students with CF they run the risk of infection transmission. This appears to be the case for this school.

    HOWEVER, the various stories I’ve read about this have not made clear what the new student’s genetic condition is. The parents have said that various tests have indicated that he has normal lung function, which I would think simplifies the issue because people with normal lung function don’t get Bcc (or P. aeruginosa) lung colonization.

    Until this morning, I was completely unaware that there were CF alleles that someone can be homozygous for, or heterozygous with 2 different mutant alleles, that result in some CF symptoms but normal lung function. I say this as a researcher of CF pathogenic bacteria, so it’s not the most common knowledge and I can easily see the school district not knowing this.

    So the student either has some set of CF alleles that leave him with normal lung function, or he’s heterozygous carrier like ~5% of the European descended population. If he’s simply a carrier I cannot imagine his parents filling out a health form and noting that fact, but its possible I suppose.

    Either way, if he has normal lung function then I don’t see a need for segregation. Presumably to be safe they’d want to verify periodically that there hasn’t been an onset of lung dysfunction, but I assume that is part of medical treatment for someone with CF in the first place.

  • Razib Khan

    #26, thanks. you know your shit, and it shows. appreciated.

  • Dm

    #26 I was completely unaware that there were CF alleles that someone can be homozygous for, or heterozygous with 2 different mutant alleles, that result in some CF symptoms but normal lung function

    It’s actually relatively well known – but of course completely irrelevant for the specific field of lung infection etiology / treatment studies – that milder CTFR alleles cause pancreatic issues almost inevitably, but lungs may remain healthy. There was a case study of twins one of whom developed pancreas and severe lung problems, while the other one has pancreatic problems but no Pseudomonas infection and no need for antibacterial regimen (as far as I recall they weren’t id twins, because the discussion dwelled on non-CTFR trans acting genetic factors)

    “Leaky” splice mutations are especially fickle, with expression of full-length mRNA species varying from patient to patient and from tissue to tissue. In CTFR, partially penetrant splice mutations involve both canonic splice site consensi (for example poly-pyrimidine repeat length variants in the weak-ish splice acceptor of exon 9) and extraneous splice junctions (like a well-studied SNP which creates an alternative junction in the middle of an intron, many kb’s away from the exons; it results in a partial inclusion of a spurious exon, and therefore the functional mRNA level goes down). I think the rule of thumb is that until one loses 75% of “correct” mRNA species in the lung epithelium, the lungs stay healthy; and only after 90%+ mRNA is lost, then the lung disease becomes inevitable.

  • JohnV

    @27 Thanks Razib, glad I could contribute.

    @28 See all the neat things I miss being a bacteriologist! Thanks a lot DM. Next proposal I submit will have a better introduction, that’s for sure.

  • Marie

    @#26 and 28. Thanks for the explanation. I learned a lot. My guess is that “being watched” is a euphmism for “he has had every test under the sun performed, including analysis of pathogens (if possible) and is probably a case study in a medical journal somewhere.” It is implied that the 2 children with CF do not carry Bcc organisms. What a waste of time if everyone concerned is Bcc negative.


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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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