Acute lymphoblastic leukemia in a patient with constitutional chromosome 1pter-p36.31 duplication and 1q43-qter deletion.

Chromosome 1 is the largest of all human chromosomes, containing 3141 genes. It is linked to 890 known genetic diseases including congenital hypothyroidism, hemochromatosis, and prostate cancer. Recognized deletion and duplication syndromes have been described. Deletions in the short arm (p) of the chromosome have been identified in tumors of the brain and kidneys. Duplications in the long (q) arm of the chromosome are reported in myelodysplastic syndromes. Solitary 1p36 deletion or 1q42 duplication are rarely reported entities and their associations with malignancy have not been characterized. We report a case of a child with constitutional 1pter-p36.31 duplication and 1q43-qter deletion who developed acute lymphoblastic leukemia (ALL). The patient's oncologic presentation and subsequent clinical course raise the question of the association of the underlying genetic abnormality and its malignant potential, specifically in relation to ALL. Acquired chromosome 1 deletions and duplications have been well described in other malignant diseases. Constitutional chromosome 1p duplication and 1q deletions have not been described with ALL.