We report on a microcephalic, growth-retarded newborn girl without major anomalies who has chromosome instability in lymphocytes and fibroblasts. Frequent involvement of bands 7p13, 7q34, 14q11, and 14q32 suggested the diagnosis of ataxia telangiectasia (AT) or a related disorder. Supportive evidence was radioresistant DNA synthesis in fibroblasts and radiation hypersensitivity of short-term lymphocyte cultures. Follow-up for nearly 4 years showed largely normal development, and no signs of telangiectasia, ataxia, or immunodeficiency. Serum AFP levels turned from elevated at age 5 months to normal at age 2 years. We propose that our patient belongs to the expanding category of "AT-related" genetic disorders, probably to the Nijmegen breakage syndrome.

We report on a patient with primordial growth retardation, mental retardation, and minor anomalies (triangular face, open sagittal suture, frontal bossing, telecanthus, upturned nose, micrognathia, and small mouth with downturned corners). The diagnosis of Russell-Silver syndrome (RSS) had been considered but was abandoned when cytogenetic evaluation showed a partial trisomy 1q or duplication 1q (46,XY,15, + der(15)t(1;15)(q42;qter). Data from another 5 reports of dup(1)(q42-->qter) do not allow delineation of a typical syndrome. However, individuals with dup(1q), del(15q), and Russell-Silver syndrome share common manifestations (i.e., low birth weight, growth retardation, triangular face, low set/abnormal ears, micrognathia, renal anomalies.

To investigate further the role of the hypothalamic luteinizing hormone releasing factor (LRF) pulse generator and the pituitary LRF receptor in the regulation of gonadotropin secretion and gonadal steroidogenesis in the ovine (O) fetus and neonatal lamb, we measured the increment (the difference between the concentration of plasma LH at time 0 and peak LH) in oLH (delta oLH) and oFSH (delta oFSH) responses to a potent LRF agonist, D-Trp6Pro9NEt-LRF (LRF-A), after consecutive daily doses in 17 ovine fetuses (six females, 11 males) and in 15 neonatal lambs (six females, nine males). Seven of the lambs had been studied as fetuses. In addition, plasma concentrations of testosterone (T) and androstenedione (delta 4A) were measured in nine male fetuses. After a stimulatory response to the first dose of LRF-A, the mean delta oLH and delta oFSH responses in the 106- to 118-d gestation fetuses of both sexes were significantly suppressed by the fourth dose and in the neonatal lamb by the second dose. Suppression was sustained throughout the duration of LRF-A therapy which included the gestational interval when the fetal pituitary exhibits its greatest responsiveness to an acute dose of synthetic LRF. The duration of oLH and oFSH suppression after cessation of LRF-A therapy was studied by measuring the delta oLH and delta oFSH responses to LRF before and at intervals after LRF-A therapy. In the fetus, the delta oLH and delta oFSH responses remained significantly decreased 7-8 d after the agonist was discontinued.(ABSTRACT TRUNCATED AT 250 WORDS)

No abstract