A rare non-Robertsonian translocation involving chromosomes 15 and 21.

Context: Robertsonian translocations (RT) are among the most common balanced structural rearrangements in humans and comprise complete chromatin fusion of the long arm of two acrocentric chromosomes. Nevertheless, non-Robertsonian translocation involving these chromosomes is a rare event.

Case Report: We report a de novo unbalanced translocation involving chromosomes 15 and 21.

Autism spectrum disorder in a girl with a de novo x;19 balanced translocation.

Balanced X-autosome translocations are rare, and female carriers are a clinically heterogeneous group of patients, with phenotypically normal women, history of recurrent miscarriage, gonadal dysfunction, X-linked disorders or congenital abnormalities, and/or developmental delay. We investigated a patient with a de novo X;19 translocation. The six-year-old girl has been evaluated due to hyperactivity, social interaction impairment, stereotypic and repetitive use of language with echolalia, failure to follow parents/caretakers orders, inconsolable outbursts, and persistent preoccupation with parts of objects.

Acute monocytic leukemia and multiple abnormalities in a child with duplication of 1q detected by GTG-banding and SKY.

Patients with 1q duplication have demonstrated a wide range of multiple congenital abnormalities. Alterations involving this chromosomal region have being described in hematopoietic malignancies and a series of candidate genes that may be associated with neoplasias have been mapped in this region. We describe a case of partial trisomy 1q "syndrome" and acute monocytic leukemia.

B lineage acute lymphoblastic leukemia transformation in a child with juvenile myelomonocytic leukemia, type 1 neurofibromatosis and monosomy of chromosome 7. Possible implications in the leukemogenesis.

This report describes the case of an 8-month-old infant with a diagnosis of juvenile myelomonocytic leukemia (JMML) and type 1 neurofibromatosis that presented progression to B lineage acute lymphoid leukemia (ALL). The same rearrangement of gene T-cell receptor gamma (TCR gamma) was detected upon diagnosis of JMML and ALL, suggesting that both neoplasias may have evolved from the same clone. Our results support the theory that JMML may derive from pluripotential cells and that the occurrence of monosomy of chromosome 7 within a clone of cells having an aberrant neurofibromatosis type 1 (NF1) gene may be the cause of JMML and acute leukemia.