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Combinations are possible, i.e. several loci may be requested in one message.
?Only one SMP_REQ can be open for a patient / donor pair (please see also the General section about duplicate requests).
The appropriate action if the typing request cannot be accepted or has to be changed by the recipient, e.g. due to national rules, is to inform the requesting side what was done. If only the resolution was changed (the sender will receive something different than ordered - either more or less) or only a part of the requested loci were accepted (the sender will only receive parts of what was ordered): send a MSG_RSP containing the warning.
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