Nijmegen breakage syndrome (NBS), a rare autosomal recessive condition also known as ataxia telangiectasia (AT) variants VI and V2, is characterised by microcephaly, typical facies, short stature, immunodeficiency, and chromosomal instability. We report the clinical, immunological, chromosomal, and cell biological findings in 42 patients who are included in the NBS Registry in Nijmegen. The immunological, chromosomal, and cell biological findings resemble those in AT, but the clinical findings are quite different. NBS appears to be a separate entity not allelic with AT. (JMed Genet 1996;33:153-156)

We review 43 p atie n ts (15 new, 28 literature) w ith the branchio-oculo-facial (BOF) syn drome, w h ic h has a d istin ctiv e phenotype ran g in g from m ild to severe forms, consist in g of eye, ear, oral, a n d craniofacial anom alies. V irtu a lly u b iq u ito u s and possibly pathognom onic are the cervical/infra-auricu la r sk in defects. M uch less common are supra-auricular defects occurring as iso late d anom alies or w ith cervical defects. Re gardless of lo catio n , these lesions may have aplastic, "hem angiom atous," or otherwise abnorm al overlying skin, and d ra in in g sinus fìstulae. R e n a l m alfo rm atio ns are frequent, b u t congenital h e a rt a n d central nervous system defects are rare* Psychomotor per form ance is u s u a lly norm al, b u t develop m ent delays, h y p o to n ia , and visual, hearing, and speech problem s are common. Autoso m al d o m in a n t in h e rita n c e seems likely. Overlap betw een the B O F and branchio-otorenal syndromes has been observed, b u t elu cidation o f its m o le cu lar basis is not yet available. This article also discusses 5 p a tients w ith aty p ical m anifestations consid ered to be possibly affected or probably u n affected, w ho are sufficiently unusual to be excluded from the fin a l data analysis.

Oculo-dento-digital dysplasia (ODDD, OMIM no. 164210) is a pleiotropic disorder characterized mainly by ocular anomalies, varying degrees of finger and toe syndactyly, and enamel defects. It is caused by missense mutations in the gene coding for the gap junction protein connexin 43 or GJA1. Other types of mutations have so far not been reported. Here we describe a Dutch kindred with ODDD showing a new symptom, palmoplantar keratoderma, and associated with a novel 2-bp deletion mutation of GJA1. The dinucleotide deletion 780_781delTG is located in the cytoplasmic C-terminal loop and leads to a frameshift. This is predicted to lead to the production of a slightly truncated protein with 46 incorrect amino acids in the C-terminal cytoplasmic loop (C260fsX307). This novel mutation may explain the presence of skin symptoms.

The role of GH insufficiency in the pathogenesis of short stature in Noonan syndrome is unclear. Cross-sectional study. Seventeen patients with Noonan syndrome (13 boys, 4 girls; aged 4.8-13.3 (mean 9.2) years) and short stature before start of GH treatment. Spontaneous 12-h overnight GH secretion by continuous sampling analysed using Pulsar, plasma IGF-I and IGFBP-3 levels, and 24-h urinary GH excretion were measured at start of GH treatment. A glucagon stimulation test was performed. Height and height velocity were monitored before and after 1 year of GH treatment. IGF-I and IGFBP-3 were remeasured after 1 year of GH treatment. Nine of the 17 children had a mean overnight GH concentration below the lower limit of the normal range. In six of the 17 patients, overnight GH profiles showed high trough GH concentrations. Glucagon stimulation tests were normal in 16 of the 17 patients. Mean IGF-I level was below normal (-0.4 SD). None of the parameters regarding GH secretion obtained from the overnight profile or provocative test was related to height or height velocity, nor to first year response to GH treatment. IGF-I and IGFBP-3 did not correlate with any of the GH secretion data. IGF-I and IGFBP-3 were related to height and height velocity at the start of GH treatment (r = 0.53 (P < 0.01) and r = 0.61 (P < 0.03) respectively). Rises in IGF-I and IGFBP-3 under GH treatment were related to the increment in height velocity (r = 0.70 (P < 0.01) and r = 0.71 (P < 0.02) respectively). Abnormalities in GH secretion are frequent in patients with Noonan syndrome and short stature. These abnormalities were not related to auxology at start of or response to GH treatment. Clinically GH insufficiency is not important in Noonan syndrome and monitoring spontaneous GH secretion is not necessary before the start of GH treatment.

We report on a male patient born to healthy, first cousin, Moroccan parents. During the pregnancy growth retardation was observed. Birth weight, length, and OFC were all well below the 3rd centile. Facial anomalies, microphthalmia, cleft palate, small penis, and flexion contractures of large joints were noted. Cerebral MRI showed dysmyelination. The clinical course was characterised by feeding difficulties, growth failure, lack of development, photosensitivity, and death at 7 months. The main differential diagnoses were COFS syndrome and early onset Cockayne syndrome (CS). UV exposure of cultured fibroblasts showed inhibition of nucleic acids synthesis. Further DNA repair studies showed extreme cellular sensitivity to UV and xeroderma pigmentosum (XP)-like defective nucleotide excision repair (NER), which in combination with the clinical symptoms indicated the very rare XP-CS complex. Complementation analysis showed that the XPG gene is affected in this patient. In cases suspected of having COFS syndrome and early onset CS, extensive DNA repair studies are needed to reach the definitive diagnosis, thereby allowing reliable genetic counselling and prenatal diagnosis. (J Med Genet 1996;33:607-610)