ABSTRACT
We present clinical outcome, through several years of follow-up, of 4 mentally retarded patients, each with a small interstitial deletion in the long arm of chromosome 2, within a region on which clinical reports are infrequent. Our patient 1 was found to have del(2)(q22.3q23.3); patients 2 and 3, del(2)(q23.3q24.2); and patient 4, del(2) (q24.2q31). By comparison of our cases with each other and with those previously published with comparable interstitial deletion, we attempted to identify characteristic clinical findings. Short neck with excessive cervical skin was seen with monosomy of chromosome 2 bands q22.3-q23.3, while hypertrichosis and a peculiar high pitched cry were seen with monosomy of chromosome 2 bands q23.3-q24.2. As suggested by Moller et al. [1984: Hum Genet 68:77-86], a cleft between the first and second toes was seen with monosomy of chromosome 2 bands q24.2-q31. In addition, seizure disorder was present in patients 1 and 4 (with the more proximal and distal deletions, respectively).
Subject(s)
Chromosome Aberrations/genetics , Chromosome Deletion , Chromosomes, Human, Pair 2 , Adult , Child , Chromosome Disorders , Female , Follow-Up Studies , Humans , Intellectual Disability/genetics , Male , Seizures/geneticsABSTRACT
Treatment of C57BL/6 J (B6) and NON male mice with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) resulted in a high incidence of bladder cancer. The mean survival period, however, differed significantly by strain: 481+/-219 days in B6 (n = 31) and 203+/-119 days in NON (n = 30) (P < 0.0001). Major causes of death were renal failure due to obstruction of the urinary tract, or local invasion of tumors. The fact that the BBN-treated NON x B6 reciprocal F1 mice had survival periods as short as those of the parental NON mice suggests a genetically dominant susceptibility in NON or recessive resistance in B6. A linkage analysis of 248 back-cross mice to B6 suggested at least two quantitative trait loci determining the length of the survival period: one was mapped close to D2Mit260 (logarithm of odds, LOD, score 2.21), a microsatellite marker locus 83 cM from the centromere on chromosome 2, and another was close to D6Mit159, 7 cM from the centromere on chromosome 6 (LOD score 2.51).
Subject(s)
Urinary Bladder Neoplasms/genetics , Animals , Butylhydroxybutylnitrosamine/pharmacology , Chromosome Mapping , Genetic Linkage , Genetic Predisposition to Disease , Male , Mice , Mice, Inbred Strains , Microsatellite Repeats , Quantitative Trait, Heritable , Survival Analysis , Urinary Bladder Neoplasms/chemically induced , Urinary Bladder Neoplasms/mortalityABSTRACT
A complex de novo translocation was found in leukocytes and fibroblasts from a boy with mental retardation and minor abnormalities. The 45,XY chromosome constitution found in all cells was initially interpreted from routine G- and Q-banding techniques as a balanced translocation of part of the short arm of 12 to the short arm of 15 and of the long arm of 21 to the short arm of 12. With additional staining techniques and use of prometaphase chromosome preparations, it was determined that the distal portion of band 12.3 of the short arm of chromosome 12 was missing from the 12/15 and the 12/21 translocation chromosomes. This interpretation was confirmed by a decreased concentration of the LDH-B subunit in lactate dehydrogenase isozymes of the patient's fibroblasts, consistent with his being hemizygous for the LDHB locus.
