Noncoding copy-number variations are associated with congenital limb malformation

PurposeCopy-number variants (CNVs) are generally interpreted by linking the effects of gene dosage with phenotypes. The clinical interpretation of noncoding CNVs remains challenging. We investigated the percentage of disease-associated CNVs in patients with congenital limb malformations that affect noncoding cis-regulatory sequences versus genes sensitive to gene dosage effects.MethodsWe applied high-resolution copy-number analysis to 340 unrelated individuals with isolated limb malformation. To investigate novel candidate CNVs, we re-engineered human CNVs in mice using clustered regularly interspaced short palindromic repeats (CRISPR)–based genome editing.ResultsOf the individuals studied, 10% harbored CNVs segregating with the phenotype in the affected families. We identified 31 CNVs previously associated with congenital limb malformations and four novel candidate CNVs. Most of the disease-associated CNVs (57%) affected the noncoding cis-regulatory genome, while only 43% included a known disease gene and were likely to result from gene dosage effects. In transgenic mice harboring four novel candidate CNVs, we observed altered gene expression in all cases, indicating that the CNVs had a regulatory effect either by changing the enhancer dosage or altering the topological associating domain architecture of the genome.ConclusionOur findings suggest that CNVs affecting noncoding regulatory elements are a major cause of congenital limb malformations.     

Usher syndrome type I associated with bronchiectasis and immotile nasal cilia in two brothers.

Usher syndrome type I is an autosomal recessive disease characterised by congenital sensorineural deafness, involvement of the vestibular system, and progressive visual loss owing to retinitis pigmentosa. Here we report the association of this disease with bronchiectasis, chronic sinusitis, and reduced nasal mucociliary clearance in two sibs and we suggest Usher syndrome type I could be a primary ciliary disorder.     

Severe lower limb defects in exstrophy of the cloaca

We present here a patient with exstrophy of the cloaca associated with severe lower limb defects. The limb malformations include, on the right, a split foot with distal separation of the tibia and fibula, and on the left, attachment of the lower half of the left leg with a two-toed foot at nearly a right angle to the mid left thigh. A review of the literature indicates that 17-26% of patients with cloacal exstrophy also have lower limb defects. We hypothesize that cloacal exstrophy and associated lower limb defects have a related pathogenesis and that both are related to deficiencies of caudal mesoderm or mesodermal differentiation signals. More cases of exstrophy of the cloaca with limb defects need to be reported to better characterize the limb anomalies and to more precisely determine their frequency.     

Smith-Fineman-Myers syndrome in two brothers.

We report on 2 brothers with a distinctive facial appearance, severe mental retardation, short stature, cryptorchidism, asplenia in one, dramatic failure to thrive, early hypotonia, and later hypertonia all suggestive of the Smith-Fineman-Myers syndrome. All 5 of the reported cases have been males, suggesting X-linked inheritance.     

Lethal congenital non-spherocytic,non-immune hemolytic anemia with genital and other anomalies in two brothers

Non-consanguineous healthy parents had 2 boys with severe, non-spherocytic, nonimmune hemolytic anemia, abnormalities of their external genitalia, flat occiput, dimpled earlobes, deep plantar creases, and increased space between their first and second toes. The birth of these children was separated by a spontaneous abortion at 3 months and delivery of a normal girl. We propose that these boys have a heretofore undescribed autosomal or X-linked recessive syndrome. © 1995 Wiley-Liss, Inc.     

Neonatal testicular torsion in two brothers.

Two brothers presenting neonatal testicular torsion are reported. The findings suggest an autosomal or X-linked recessive pattern of inheritance for the anatomical underlying anomaly.     

Two brothers with heart defects and limb shortening: case reports and review.

Two male Arab sibs are reported with congenital heart disease and skeletal malformations. Other published case reports sharing some features in common with these brothers are considered. However, clinical and radiological features in these boys are distinct enough to represent a new cardioskeletal syndrome.     

Severe mental retardation, cataracts, short stature, and primary hypogonadism in two brothers

Two severely mentally retarded brothers are described who had a similar facial appearance, cataracts, short stature, minor digital abnormalities, and primary hypogonadism. Their parents were first cousins. Numerous laboratory investigations failed to elucidate a basic metabolic cause for their disorder.     

Microcephaly, short stature, and developmental delay associated with a chemotactic defect and transient hypogammaglobulinaemia in two brothers.

Two brothers presented with unusual facial features, microcephaly, developmental delay, and severe postnatal growth retardation. They both developed eczema in infancy and have had recurrent infections. Additional physical findings in both boys included hypogonadism, flexion contractures, hypoplastic patellae, and scoliosis. Their facial similarity was striking with sloping foreheads, beaked noses, large, protruding ears, and micrognathia. Low levels of serum gammaglobulins and defective chemotaxis were present in both boys in infancy. The hypogammaglobulinaemia was transient and improved, reaching normal levels by 3 1/2 years and 15 months, respectively. Defective chemotaxis and recurrent infections have persisted to the present. Both parents were normal. The mode of inheritance was not clear, as both X linked and autosomal recessive patterns were possible. Although patients with congenital malformations who also had immunodeficiency have previously been reported, immune system abnormalities, especially those of a transient nature, may frequently go unrecognised.     

Congenital horizontal gaze palsy and kyphoscoliosis in two brothers.

In a sibship of 11, two brothers with a congenital complete horizontal gaze palsy developed severe kyphoscoliosis. No-one else in the family has a gaze palsy or comparable skeletal abnormalities. Since the parents are first cousins, an autosomal recessive mode of inheritance seems likely.     

Cystic dysplastic kidneys associated with Dandy-Walker malformation and congenital hepatic fibrosis. Report of two cases

The combined abnormalities of Dandy-Walker malformation, congenital hepatic fibrosis, and generalized cystic dysplastic kidneys were found in two sanguineously unrelated premature babies. This type of cerebrohepatorenal malformation is certainly unique and is generally diagnosed based on the characteristic renal lesion. Remarkably, similar renal lesions have been found in Meckel's syndrome, Goldston's syndrome, and Miranda's syndrome. The present cases can be distinguished from Meckel's syndrome on the basis of the presence of Dandy-Walker malformation and the absence of polydactyly and occipital meningoencephalocele. Although the authors' cases resemble the latter two syndromes in terms of the presence of Dandy-Walker malformation, it is tentatively considered that the distinct triads found in the present cases could represent a new variant of a multiple malformation syndrome with generalized cystic dysplastic kidneys. The etiology of these cases remains unclear, but a genetic factor, which has been suggested as for other syndromes, might be involved.     

Familial left ventricular hypertrabeculation in two blind brothers.

So far, left ventricular hypertrabeculation (LVHT) has been described to occur only sporadically. In a 49-year-old man with Leber's hereditary optic neuropathy (LHON) due to the primary LHON mutation G3460A, arterial hypertension was reported since 2000 and palpitations since 1995. ECG revealed Wolff-Parkinson-White syndrome. Transthoracic echocardiography and cardiac MRI showed myocardial thickening and LVHT. Pindolol markedly improved the cardiac abnormalities. Surprisingly, LVHT was also found in the 50-year-old brother of the index patient who also had LHON and also carried the G3460A mtDNA mutation. This brother also had Wolff-Parkinson-White syndrome and myocardial thickening, but without hypertension. It is concluded that LVHT, previously described to occur only sporadically, may be hereditary in single cases.     

Agenesis of the corpus callosum in two brothers.

Two brothers with developmental delay and unusual cranial configurations were found to have agenesis of the corpus callosum (ACC) by CT scan. Six published families in which ACC occurred in the absence of extracranial malformations are reviewed. No single mode of inheritance can account for all of these familial cases. This family illustrates the value of CT scanning in evaluating children with developmental delay.     

Movement and mood disorder in two brothers with Gaucher disease

Gaucher disease (GD) is a lysosomal storage disorder with a wide spectrum of phenotypic presentations. We report the case histories of two adult brothers with GD who developed both parkinsonism and psychiatric symptoms. Direct sequencing and real-time polymerase chain reaction were used to establish that the patients were homozygous for mutation L444P. While parkinsonism has been described previously in GD, these patients had atypical features, including a complicated mood disorder. The comorbidity of GD and a mood disorder is a new finding, as psychiatric manifestations of GD have been described rarely. The etiology of the mental illness could be related to the processes contributing to the development of parkinsonism.     

Anomalous coronary arteries arising from the aorta associated with sudden death in infancy and early childhood. An autopsy series

Anomalous coronary arteries arising from the aorta are a recognized cause of myocardial ischemia and sudden death. Death has been precipitated by exercise in most cases. We present the results of an autopsy study in which sudden and unexpected deaths associated with coronary anomalies were found in three children (less than 2 years of age). In two cases, death was not associated with exercise. In two case, the myocardium was morphologically normal, and in the third case, there was an extensive recent anterior myocardial infarct with a background of established fibrosis. Coronary artery anomalies may be easily overlooked in this age group because of small vessel size and difficulty in dissection; this is particularly so when there are normally placed ostia. One consequence of this is potential for confusion with sudden infant death syndrome.     

Microcephaly and intracranial calcification in two brothers

Sibs are reported with severe congenital microcephaly, spasticity, and seizures. Both had extensive intracranial calcification.