Haemoglobin Gene Variants
Guidance for Users
Information is provided both in a very simple format and in detail.
The materials can be used as aids to the counselling process, but also have other uses.
- For each carrier diagnosis there is one sheet. Each person with a carrier diagnosis should receive the appropriate sheet or equivalent written information. A copy should also be sent to the family doctor. These sheets are also suitable for issue by the diagnosing laboratory, to accompany results.
- For precise carrier diagnoses there is also a 15-page booklet with full information.
- The reproductive implications of each carrier diagnosis (if a carriers partner is not a carrier, carries the same haemoglobin disorder or carries a different haemoglobin disorder) are also explained on single sheets. Whenever a carriers partner is tested, the appropriate sheet should be issued to the couple whether or not the results indicate a genetic risk. A copy should also be sent to the family doctor.
- For "risk combinations" - carrier combinations that generate a risk of a child with a significant haemoglobin disorder - there is a complete booklet explaining the risk, the condition concerned, its management, and (when appropriate) possibilities for prevention. The relevant booklet can be used as a aide in the counselling process, and given to each carrier couple to keep after counselling. Space is provided in these booklets to record the couples precise haematological and DNA results, and the issuing centre. The aim is to promote prompt and accurate risk assessment, and continuity of care in the future.
Carriers should be advised to keep all information issued with their personal papers for future reference, especially in case of a pregnancy.
Please contact APoGI if you are uncertain about the appropriateness of a particular document to a particular case.
Safeguards for Health Professionals
The information materials are correct only if the diagnosis is correct. There is usually little doubt about a diagnosis provided by an experienced laboratory, but mistakes can happen. We recommend the following rules in counselling for haemoglobin disorders:
- Always see a copy of the original results, or a haemoglobinopathy card giving the address of the centre where the diagnosis was made, or a letter in which the results were written by a competent person, before providing counselling. Errors are easily made if counselling is based on hearsay, however authoritative the source of verbal information may be.
- If you are not sure that the laboratory where the test was done is definitely reliable, arrange for a repeat test before providing counselling. If the diagnosis has been made in a laboratory other than the one you habitually work with, especially one in an area where there are not many people in ethnic groups at risk, consider carefully if the results are really reliable. Errors can occur when there is not a large haemoglobinopathy workload or if recognised recommendations for screening are not followed. They can happen even in a laboratory that belongs to a quality control programme or is sited in a university hospital. Repeat the test if there is any doubt at all.
All materials are provided subject to the APoGI Disclaimer.
Problems or further enquiries? Contact APoGI.
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