A-Z

Screening for sickle cell and beta thalassaemia

Explaining genetics and risk

One of the first tasks in counselling people who discover they are or their baby is a carrier is to explain the difference between being a carrier and having the condition. Many people are worried at first that they or the baby will be seriously ill and need reassurance that this is not so.

Having reassured people that being a carrier does not make them ill, a key task for professionals is to explain how recessive conditions such as sickle cell disorders and beta thalassaemia major are inherited and what the risks are of having a baby affected by the condition. Most people we talked to felt they had been given very good counselling to help them understand how the genes are passed on, and particularly valued the use of drawings or diagrams to demonstrate inheritance.

 

Professional learning: It helped to have a diagram to explain inheritance, and reassure her that...

Professional learning: It helped to have a diagram to explain inheritance, and reassure her that...

Age at interview: 32
Sex: Female
SHOW TEXT VERSION
PRINT TRANSCRIPT
[Sighs] I think he was about four days old now and everything was still a blur.  I just remember it's the normal heel prick test they do, but I do remember her saying that they will send it for the sickle cell test. So it was, I was informed of it and I was like, 'That's fine, not a problem, whatever tests he needs, then have them.' Like I say I don't mess. It's your kids, isn't it? So.

Hmm. So you did know that it was one of the things that they were locking for?

Yeah, yeah. But I was just shocked that it come back with anything [laughs]. Because he was just a normal, he's just a normal healthy baby. He looks normal. He's happy and...

And when she came to talk to you, what things did she run through with you? Things like the, sort of the inheritance pattern?

Yeah, how it can come down, and what's the chance of - because you've got like figures of little - not animals - little people figures and it shows you that a full blown sickle cell parent only passes the trait. 

Yeah, two sickle cell, two trait parents have the chance of passing on full blown, and are more likely to pass on just the trait.  But if you're just a sickle cell trait parent then you've got less - you're not likely to pass on the full blown sickle cell. So it was a case of, 'We're all only trait. I haven't got to worry about them. They're not going to full blown. But yeah, it showed me a lot and I understood a lot more and I knew that there's only that one-in-four chance of me then passing it on to any more children, if I do have any more children.
 
 

Professional learning: Her midwife did not tell her much about her results, but the specialist...

Professional learning: Her midwife did not tell her much about her results, but the specialist...

Age at interview: 22
Sex: Female
SHOW TEXT VERSION
PRINT TRANSCRIPT
Well, the lady at the sickle cell medical centre, I've forgot her name now, she explained it in great detail, as the midwife didn't really go into it. I suppose they just left it for them to do, really. But they should have gone into a little bit more about it really, because they do know about it. So they should have explained it, about it more and said, 'Right, you know, you're going to have an appointment. This is what they're going to say,' you know, but they didn't. So the lady at the clinic went into everything in detail. She was really nice, a very nice lady.

And did you und-, feel you understood her?

Oh definitely, yeah, because she'd go through it a couple of times and she'd say, 'Look, you know, do you understand that? Otherwise we'll go through it again.' And she had a little diagram and, you know, wrote everything out and yeah, she was marvellous, really nice. Even though I was upset at the time, she was a nice person and, you know, she explained everything in great detail. And if my partner did have the condition, she would have obviously helped with support and, you know, going through all the bad bits, should we say [laughs].
 
 

Professional learning' She was very satisfied with the counselling she received. She had not...

Text only
Read below

Professional learning' She was very satisfied with the counselling she received. She had not...

Age at interview: 24
Sex: Female
HIDE TEXT
PRINT TRANSCRIPT
And what were your general feelings about the service that you got at the counselling centre?

Oh, just fantastic, yeah. It's fantastic. And so I think that was what helped me make up my mind, I think, to make a decision to go and have the CVS done.

Tell me how that it helped you?

Because I didn't know that you only get one in four chances of having a sickle cell child, so I just thought it's either you have AS [sickle cell carrier] or SS [sickle cell anaemia] child. I didn't know you could even have an AA [not a carrier] child. So she explained everything and, yeah, it really enlightened me, so yeah. And I just thought, 'Okay, one in four chances, [laughs] I might as well take a chance here.'

Do those risk figures kind of mean anything to you, I mean when someone says 'one in four'?

Yeah, because she did a little diagram, and so I knew I only had, I only have a chance of having an AA or an SS, and I have two chances of having an AS child, so it's quite high for me at that point. I needed something, yeah.
 

However, some people's responses showed that they had misremembered some information or had added their own meanings or interpretations. For example, one person identified the risk of two carriers having an affected child as 1 in 10 rather than 1 in 4, and several people who knew they were carriers used expressions such as 'I've got thalassaemia but it's not major'. One mother believed that having CVS in one pregnancy had, in some way, caused her daughter's beta thalassaemia major' 'She is like this because of that [CVS]… I think the needles that they put inside, or the sample they take, they take some flesh or something, I don't know.' Other examples included:

'I thought she [daughter who is a beta thalassaemia carrier] will have less blood from one side, maybe that's why she doesn't eat.'

'[Beta thalassaemia] is like a blood condition, like it happens in our Pakistan because of dirt, because of disease, that's why there is thalassaemia. Some people catch it.'

'We understood that one of us had got bad blood, as such, and one of us had got good blood.' 

'Normal blood cells are round, aren't they? Whereas sickle cell blood cells are spiky. So that hurts as it's going round your blood system.'

The National Screening Programme recommends avoiding use of the word 'trait' (meaning 'genetic characteristic') to describe carrier status but many people interviewed were using it. A particular problem is that 'trait' sometimes becomes confused with the word 'trace', giving people a misleading impression that it is something minor or insignificant. One woman explained she had been led to believe the presence of haemoglobin S was not permanent. The family thought that she couldn't be a sickle cell carrier because she was always getting malaria as a child, and being a carrier is thought to be protective against severe malarial infection, particularly in childhood. (However, carriers are still at some risk of malaria infection). 

 

Professional learning: When she was a child her family thought she had only a tiny amount of...

Professional learning: When she was a child her family thought she had only a tiny amount of...

SHOW TEXT VERSION
PRINT TRANSCRIPT
We had to do like eight blood tests, and they took out eight, my goodness, bottles of blood from me. And they were like, oh, they were going to test for AIDS, they were going to test for blood group, they're going to test for so many stuff. I was like, 'OK, no problem.' I actually thought I was AA [not a carrier], because when I was little, my mum told me, they said the S was so small it was going to leave. And I always used to have malaria. So actually I was so confident that it was AA, you know, so I was like they could take as much blood as they want, you know? 

But you said they'd said there was a tiny bit of S?

Very tiny S. Because in Africa they believe if you're AA you always have malaria, but if you have AS you're stronger. You never fall sick. So when the S [haemoglobin S] - according to the doctor in Africa the S will go. And I always had the, I always had the tendency that I always had malaria. October was my worst month in Africa. I always had malaria. So my mum was like, 'Oh yes, the S had gone'. It was now AA. That's the problem. But it wasn't a problem. Well, that's what I thought.

So has anybody talked to you about that since and, and about why, you know whether that was true, or whether it was the testing hadn't picked it up properly or?

Nobody has, but to me, I know back then, twenty-six years ago, we didn't really have like equipment you guys have now, you know? So I know being Africa, they could have made their mistake, you know? We just take it that, 'Oh yes, Africa wasn't really developed then, so they must have made a mistake.'

Footnote' Although being a carrier of sickle cell does seem to be protective against severe malarial infection in many people, particularly during childhood, there is still a risk of malaria infection. Your carrier status does not change during your lifetime.

It may help some parents to be told that being a carrier does have some health advantages. As well as protection against malaria, there is some evidence that being a beta thalassaemia carrier reduces the risk of coronary heart disease.

Understanding recessive inheritance is an important part of explaining why partner screening is recommended. Again, making it clear that carriers have no obvious symptoms and will not know whether they are carriers unless they are tested is essential. 

 

Professional learning: Her husband believed he could not be a carrier because he was fit and...

Professional learning: Her husband believed he could not be a carrier because he was fit and...

Age at interview: 36
Sex: Female
SHOW TEXT VERSION
PRINT TRANSCRIPT
Well, I think you just take these things for granted. You just take these things for granted, and you know, as much as I would like to protect all my children, or every pregnancy, I had my trust in my husband as well - then husband - that, you know, he must know what he's talking about. He knows this is a big chance, he wouldn't want this to happen to, you know, a child. But I never knew how, you know, ignorant he was [laughs] about all those things - so I just, I just took it for granted really.

So he actually, I mean it wasn't just that he said that 'I don't want to go for testing', he kind of said 'I'm AA.'

Yeah, he said he's AA [not a carrier] - he's ok. I think it's kind of believed to be AA is like when you're not weak, when you're not tired, you're not anaemic, you know, you're active, so that, I mean, you're a big man with big broad shoulders, with big bones, you know - you can do things that the women cannot do. So I think that, in his books, means, you know, not being sickle, not having the sickle trait. But then he has it.

What was his reaction to getting the test result?

'I think he was a bit, he wasn't sure. It's like, 'Well, if I have it, then I have it.' He just put up a front. But he kept praying, he kept, he knew in himself that if anything happened - because then I was still pregnant when we got the result - if the baby was sickle cell then that would be his fault. He knew that. And that, you know, he, [pause] he felt really guilty about that - really guilty. I mean, you know, it would have only taken you an hour to have a test done. Well then, you know? But then it was too late.

Did that cause problems between you?

Well, it didn't. It didn't really at first, because my daughter is one of those ones that kept most of her baby blood when she was a baby, so she didn't have any problems at all. But when it now comes to her going on a penicillin which has to be taken in the mornings and in the evenings, you know, we both have to take responsibility for that. When it came to wrapping her up, you know, properly for her to, you know, go outdoors in the cold, we would have to take responsibility for that. But [pause] he left, you know, everything up to me. That's the point that I had to make him realise that this is not my responsibility - although I'm the Mum, I'm the one that stays at home to look after the baby - but then this responsibility has got to be shared. That's when it dawned on him. And when he saw the amount of, you know, penicillin she had to take in the morning and in the night, it didn't augur well with him - he felt really bad. That's when he really felt it.

Did you feel angry with him?

Mmm' I wouldn't really say anger with him. I would say very sympathetic towards my daughter. I felt guilty. I felt bad. I felt, you know, as a mother I should have taken more responsibility and I didn't really feel good about myself for some time, and that really worried me a lot. I had to deal with that on its own. But thank God I've moved on from there. And that's why when I got pregnant again, after nine years, I thought I have to do this properly this time.

Footnote' often people do not realise that being a carrier does not affect your general health and you may have no idea you are a carrier unless you are tested.
 
 

Professional learning: Her partner assured her he was not a sickle cell carrier but they...

Professional learning: Her partner assured her he was not a sickle cell carrier but they...

Age at interview: 37
Sex: Female
SHOW TEXT VERSION
PRINT TRANSCRIPT
So, when you were starting to think about having children of your own'

Yeah'

'what were your thoughts about having the condition and having children?

I was excited to have children, yeah. I didn't know that - I wasn't told then, because I didn't know anything there - that I have to look for an AA [not a carrier] partner, that have AA, so I don't know. But I mean that my baby's father is very active, he like playing football. So I didn't know that. I thought that he's AA because he doesn't get sick. 

So, so when I got pregnant the doctor, the nurse told me at the hospital that I need to do a test. I said, 'Which test?' She said, 'To know if the baby' - no, she first asked me, 'The father, what type, what type is the blood'? I said, 'It's AA, I think.' Then she said about if it's not AA. I said, 'No, it's AA', because I was really arguing with her. So she told, she told me in case it is not AA this - she gave me more information that there's some test I can do to, to know if the baby is a carrier or she's actually carrying the disease. Then when I go home, I ask the baby father, my partner, what is his blood type? He said, 'It's AA', because he doesn't get sick. Anyway, didn't - before I left the nurse she told me that my partner have to do blood tests, to know, to be safe. He went to do the blood test and I was so shocked to find out he's AS [sickle cell carrier]. So I had to do the CVS test, so - and the CVS revealed the baby has sickle cell, SC [haemoglobin SC disorder]. So that's, so it's a very painful day.

Footnote' often people do not realise that being a carrier does not affect your general health and you may have no idea you are a carrier unless you are tested. Haemoglobin SC disorder is a type of sickle cell disorder in which the child has inherited hameoglobin S (sickle cell) from one parent and haemoglobin C from the other. Whilst it is a type of sickle cell disorder, it is a distinct condition. The symptoms can be similar to sickle cell anaemia, but SC disorder is often (but not always) milder in its effects than sickle cell anaemia.

Blood group is a different issue unconnected with carrier status. Everyone's blood belongs to one of four main blood groups (A, B, O or AB). If someone is given a blood transfusion, it must be from a compatible blood group, otherwise antibodies in the transfused blood will attack the existing blood cells and this could prove fatal.
 
 

Professional learning: Her partner did not understand that he could be a carrier and still be...

Text only
Read below

Professional learning: Her partner did not understand that he could be a carrier and still be...

Age at interview: 30
Sex: Female
HIDE TEXT
PRINT TRANSCRIPT

And you said you, you kind of got into blaming each other a bit?

Yeah. Yeah, saying that, he used to say, 'Oh' - because before he did the test I had to like, I had to talk to him like over like three months, four months to get him to do the blood test. Because what they said to me was like, 'Tell him to do the blood test there [abroad], and then he'll just post the result, the blood test result or whatever.' I tried to talk to him. He couldn't do it. He would keep saying, 'Oh, there's nothing wrong with me, there's nothing wrong with me. I don't want to do anything. There's nothing wrong with me.' I was like, 'Just do the blood test and bring the result.' 

So what happened was he came, because I was having like problem with, I was having like excess fluid in my, during my pregnancy. So I used to have like test, a scan every three weeks or two weeks, like go in for a scan. So the last one [laughs], the last time he came with me, that was like the last scan I had in August. And the midwife was like, 'Where is your partner? We're still waiting for this blood test from him.' And he, and I just said to the woman, I said, 'That's him standing there.' The woman just drag him up there and get him to do the blood test [laughs]. 

And we went in to do the blood test. But by the time we left there, we started fighting before we left the hospital. Because he was like, 'Why are you forcing me to do it? I don't want...' It takes me quite a lot of time to get him to do it because he was thinking there's nothing wrong with him. And I had to tell him, I said, 'You don't have to. If you've got sickle cell trait, you're not, you won't even know that you've got sickle cell trait. You have to do the blood test.' 

I told him, I said, 'I didn't even know. I only found out after. It was like I knew earlier about it because they told me that it's not something that you would be sick of.' I didn't take it so seriously. I didn't even, it's only when I had my child that I was like thinking, 'Okay, I didn't know I had something that's like so, that another person can get or whatever through that.' And he was like, 'I don't want to do a blood test. There's nothing wrong with me. Don't force me to do a blood test.' And he was even like thinking, 'Do you think I've got AIDS or whatever?' I was like, 'Don't, no, it's not that. It's just...' But it takes me quite a long time to get him to do it. Because I found out very early and he didn't, he didn't want to do it. I think he didn't do it till August. That's why I didn't find out till after she, I had the baby.

Did, did you feel angry with him at the time?

Yeah. There was one point I was like telling him, 'Okay, that's it. If you don't go and do the blood test I don't want to talk to you any more. I don't want anything to do with you any more.' There was one point I had, I actually went through that, like telling him, 'That's it. I don't, if you don't do the blood test, don't bother to call me.' 

Footnote' often people do not realise that being a carrier does not affect your general health and you may have no idea you are a carrier unless you are tested. A woman whose partner does not attend for screening can be offered a diagnostic test in pregnancy (CVS or amniocentesis) if she wishes to know for certain if the baby is affected. 
 

It is also important to explain that white people can also be carriers. Two black women with white partners had not been aware of this.

 

Professional learning: Her white partner has never been offered screening.

Professional learning: Her white partner has never been offered screening.

Age at interview: 36
Sex: Female
SHOW TEXT VERSION
PRINT TRANSCRIPT
Did your husband get tested?

No [laughs]. We didn't assume he would a carrier because he's, he's European. He's Danish. And as far as I can gather it's very rare among Scandinavians. So no, we didn't even think about it

That's interesting. And did anybody kind of follow up when you got the result and, you know, call you and say, 'Is your partner black, or do you have any reason to suppose he might need testing or'?'

No, but I suppose they had the information already, because they'd asked me during pregnancy what my partner was. So I suppose they knew that he was European, but whether or not that's the reason why nobody contacted us, I don't know.

Hmm.

No, after I got the card, there was no follow-up.

Footnote' If a woman is a carrier, the baby's father should be offered screening irrespective of family origin.
 
 

Professional learning: She does not believe her white partner needs to be tested because she...

Text only
Read below

Professional learning: She does not believe her white partner needs to be tested because she...

HIDE TEXT
PRINT TRANSCRIPT

Woman' We've not really -

Man' No.

Woman' -because he hasn't done the sickle cell. But because one, I'm not bothered about him because I know he will not be a carrier, because it's not very common in white people. It's a black people thing. So I'm not bothered. I don't think we'll be of the same blood group or anything. I don't think so. That, I'm very positive, it's not possible. Because he doesn't --

Man' We've only just touched on it, haven't we?

Women' Yeah.

Man' Very, very recently.

Woman' Yeah. You don't have any black origin in your family? No. Even if you have, it will be distant, distant, distant.

Man' Only, only maybe on my mother's side when my grandfather went away, ran away, a long time ago.

Woman' So.

Footnote' white people can also be carriers of sickle cell or beta thalassaemia. If a woman is a carrier, the baby's father should be offered screening irrespective of family origin.
 

If both parents are found to be carriers, they will need counselling on the chances of having a baby with the condition or a baby who is also a carrier or unaffected and on the fact that the chances remain the same in each pregnancy. Explaining in practice what risks of 1 in 4 or 1 in 2 mean can be difficult, and each individual will make different personal assessments. One mother with SC disorder described her optimistic outlook, comparing her 1 in 4 risk of having a baby with sickle cell anaemia to the risk of being knocked down by a car (which is in fact many times lower). 

 

Professional learning: She takes an optimistic approach to risk, and just hopes things won't...

Professional learning: She takes an optimistic approach to risk, and just hopes things won't...

Age at interview: 41
Sex: Female
SHOW TEXT VERSION
PRINT TRANSCRIPT

Video and audio clips read by an actor.

There's always risks out there. And I always look at the fact that I just I like to be optimistic. I always say, if you cross a road you can be knocked down by a car, so why shouldn't you cross the road? Just cross the road, you know. That's the way I look at things, so I always think that I should deal with things as they come, basically, rather than be afraid that, “Oh no, this will happen or that will happen”, you know. 

So I think I'm still more optimistic about thing like that… Even when I had my daughter… although she's got sickle cell anaemia, I was just still hoping in my mind, deep down, that I hope that she doesn't turn out to be, you know. So I still had that in my mind. So I had this sort of picture that was going through my mind, but I was still hoping that, “Ah, well, hopefully, you know, all this will not apply to her, basically, but I will just try my best.” My idea was that I will just keeping on trying my best, whatever thing I could do, to avoid all these things happening. I will try my best with it, you know, and read more, get more information about it.

By contrast a man whose sister had died of beta thalassaemia major regarded it as unacceptable and even irresponsible to run a risk of 1 in 4 of having a baby with the condition.

 

Professional learning: He sees a 25% risk as being like putting your child in the middle of a...

Professional learning: He sees a 25% risk as being like putting your child in the middle of a...

SHOW TEXT VERSION
PRINT TRANSCRIPT

Video and audio clips read by actors.

Father' If you are aware that you have something, if for instance you are diabetic, then you don't do certain things. You know it. And I take the same approach on this one. I know it, I cannot just say, “Oh, I don't know it”, otherwise it becomes irresponsible and...

Mother' I can't say, “It's only twenty-five per cent.” 

Father' “Only twenty-five per cent, the chances”. I was asked by relatives - not obviously my brothers, because they are too aware of what it means - but even close relatives that more or less are all practising Catholics and so on, and say, “Oh, how can you really [do] this? You know what you're doing?” And to one of them, I mean, I told her very bluntly. I said, “Well, tell me first of all what twenty-five per cent means to you.” And I say, “To me it means that I've got a four-lane carriageway, I've got a child and I put him in one of them, and I know that in one of those a car will come fast.” I say, “This is twenty-five per cent to me.” 

I said, “To you, what does it mean? Is it just a very distant equation or proportion?” I say, “Twenty-five per cent in simple terms means this. You've got a child - then if you believe, or if twenty-five per cent is such a little thing, put your child and yourself in there.” And I explained why I told 'yourself' as well. I say, “And you know that in one of those four lanes one car will come and can run you over.” She didn't say anything. And I said, “Yourself as well, to tell you that you are not only deciding the fate of your child, only for him, but for you… Both will be hurt, but you don't know who is going to be hurt more.” 

And then I add, “Do you think that it's fate to put your child in the middle of the road in a four-carriage way and know that one car is coming? This is fate?” I said, “This is irresponsible for me, or totally disrespect of life. So this is not religion.”

Last reviewed December 2018.

donate
Previous Page
Next Page