Frequency of haemoglobinopathies: a single-centre, cross-sectional study from Islamabad, Pakistan.

Thalassaemia is the most frequent hereditary disorder in Pakistan, with an estimated 8-10 million carriers. This single-centre study reported the frequency of haemoglobinopathies among 504 consecutive cases visiting Islamabad Diagnostic Centre for haemoglobin electrophoresis from July 2010 to February 2011. Haemoglobin electrophoresis was performed on cellulose acetate membrane, followed by staining and densitometric scanning of bands. A total of 143 (28.4%) subjects had haemoglobinopathies. The most predominant was thalassaemia trait (25.6%), followed by thalassaemia major (1.4%) and HbS or HbD (1.4%). The gene frequencies for thalassaemia trait and major were 0.256 and 0.0139 respectively. The study provides support for continuing efforts towards early detection and characterization of haemoglobinopathies to control the affected births in Pakistan.

Frequency of haemoglobinopathies: a single-centre, cross-sectional study from Islamabad, Pakistan

Thalassaemia is the most frequent hereditary disorder in Pakistan, with an estimated 8-10 million carriers. This single-centre study reported the frequency of haemoglobinopathies among 504 consecutive cases visiting Islamabad Diagnostic Centre for haemoglobin electrophoresis from July 2010 to February 2011. Haemoglobin electrophoresis was performed on cellulose acetate membrane, followed by staining and densitometric scanning of bands. A total of 143 [28.4%] subjects had haemoglobinopathies. The most predominant was thalassaemia trait [25.6%], followed by thalassaemia major [1.4%] and HbS or HbD [1.4%]. The gene frequencies for thalassaemia trait and major were 0.256 and 0.0139 respectively. The study provides support for continuing efforts towards early detection and characterization of haemoglobinopathies to control the affected births in Pakistan

Differential sensitivity to cryopreservation of clonogenic progenitor cells and stromal precursors from leukemic and normal bone marrow.

The survival of human leukemic and normal progenitor cells was determined after cryopreservation. Thirteen marrows from patients with acute myeloid leukemia (AML) were studied as fresh and eight as cryopreserved samples. Marrows from five normal donors were studied as both fresh and cryopreserved samples. Although the number of bone marrow mononuclear cells (BMMC) recovered after cryopreservation was always lower than that originally stored, no significant difference was observed between the clonogenic potential of fresh and cryopreserved BMMC from either the leukemic or the normal samples. When grown in long-term bone marrow culture (LTBMC), the cultures initiated with cryopreserved BMMC failed to form a confluent stroma, and the duration of nonadherent and progenitor cell production was significantly lower than that from fresh samples. However, when these cryopreserved samples were recharged onto preformed irradiated stroma, the duration of the cultures improved significantly. We conclude that it is the bone marrow stromal cells rather than the clonogenic progenitors which are sensitive to the effects of cryopreservation. Thus cryopreservation does not appear to influence the activity of AML progenitor cells. Our results also indicate that frozen marrow can be used for LTBMC experiments if cultured on a preformed stromal layer.

Persistence of an activating N-RAS oncogene mutation in clonogenic progenitor cells from an acute myeloid leukaemia patient in remission.

A patient with acute myeloid leukaemia (AML) with an activating N-RAS oncogene mutation was studied in a haemopoietic clonogenic progenitor cell assay. Individual colonies and clusters were analysed by polymerase chain reaction and oligonucleotide hybridization for the original mutation. The mutation was detected in a majority of leukaemic clusters, but also in almost half of the differentiated colonies. After chemotherapy the patient entered clinical remission. However, the mutation could still be detected in the bone marrow. Only differentiated colonies and no leukaemic clusters were grown from the remission bone marrow, but the original mutation was still detectable in almost half of the colonies.