ABSTRACT
Langer-Giedion syndrome (LGS) (OMIM 150230) is defined as a contiguous gene syndrome caused by loss of functional copies of the TRPS1 and EXT1 genes usually secondary to 8q microdeletion. Tibial hemimelia (TH) is the least common lower limb deficiency characterized by hypoplasia of the tibia with relatively intact fibula. We describe the third report of LGS with bilateral TH and an 8q23.1-q24.12 interstitial deletion. It is not possible to exclude that this association is fortuitous, but our report reinforces the suggestion of a putative gene involved in limb development in this chromosomal region interval.
Subject(s)
Chromosome Deletion , Chromosomes, Human, Pair 8/genetics , Langer-Giedion Syndrome/genetics , Abnormal Karyotype , Adolescent , Bone Diseases, Developmental/diagnostic imaging , Bone Diseases, Developmental/genetics , Bone Diseases, Developmental/pathology , Child, Preschool , DNA-Binding Proteins/genetics , Ectromelia/diagnostic imaging , Ectromelia/genetics , Ectromelia/pathology , Humans , Langer-Giedion Syndrome/pathology , Male , N-Acetylglucosaminyltransferases/genetics , Radiography , Repressor Proteins , Tibia/abnormalities , Tibia/diagnostic imaging , Tibia/pathology , Transcription Factors/geneticsABSTRACT
Benign cartilaginous tumors represent a spectrum of neoplastic processes with variable clinical and pathologic presentations. These tumors are histologically characterized by the presence of chondrocytes surrounded by a cartilaginous matrix. Few studies describe karyotypic abnormalities in these benign lesions. We report a series of 14 chondromas from a single institution. Conventional cytogenetics was performed on short term cultures from all cases. Clonal chromosome aberrations were found in nine tumors. One soft tissue chondroma contained three clones with t(6;12)(q12;p11.2), t(3;7)(q13;p12), and der(2)t(2;18)(p11.2;q11.2). Three periosteal chondromas displayed random structural aberrations of chromosomes 2, 3, 6, 7, and 11 and loss of chromosome 13. Among the enchondromas, three tumors displayed chromosome losses, one contained a complex translocation involving chromosomes 12, 15, and 21 as well as an inv(2)(p21q31),t(12;15;21)(q13;q14;q22) and a separate enchondroma showed a translocation involving chromosomes 12 and 22. Our data suggest that considerable cytogenetic heterogeneity exists among benign chondromatous tumors.
