Two cases of growth failure, microcephaly, facial dysmorphism, muscular hypertonia, and severe psychomotor retardation are described. At birth, both cases had cytogenetic mosaicism in lymphocytes and skin fibroblasts, in case 1 ring chromosome 21 and monosomy 21 and in case 2, deletion of chromosome 21 and monosomy 21. At a later age the lymphocyte karyotype changed almost completely to 46,XX, ...

Many a parent of a child with a neurogenetic condition (surprisingly) little pathological material has been available often wonders whether ’tis nobler in the mind to suffer the slings and arrows of outrageous fortune or to contemplate hope for effective treatment. With regard to Angelman syndrome, recent results from molecular biology have opened unsuspected avenues for circumventing the molec...

Autosomal dominant (Thomsen) and recessive (Becker) congenital myotonia are two different non dystrophic disorders, due to allelic mutations of the muscle chloride channel gene, located on chromosome 7q35. More than two thirds of the muscle chloride channel gene mutations occur independently in unique families and cause the recessive form of the disease. Becker disease is more common and severe...

The clinical phenotypes of maternal and paternal uniparental disomy of chromosome 14 (UPD14) are attributed to dysregulation of imprinted genes. A large candidate locus exists within 14q32, under the regulation of a paternally methylated intergenic differentially methylated region (IG-DMR). We present a patient with clinical features of maternal UPD14, including growth retardation, hypotonia, s...

Hemihypertrophy, or hemihyperplasia, is a condition in which there may be asymmetrical overgrowth of the cranium, face, trunk, and/or limbs on one side of the body. There may also be asymmetrical visceromegaly on the ipsilateral or contralateral side. Hemihypertrophy may occur in isolation, hence the term “isolated hemihypertrophy (IH)”, or as part of a number of overgrowth syndromes in which o...

Mandibuloacral dysplasia (MAD) is a rare autosomal recessive disorder characterized by postnatal growth retardation, craniofacial anomalies, skeletal malformations, and mottled cutaneous pigmentation. Hutchinson-Gilford Progeria Syndrome (HGPS) is characterized by the clinical features of accelerated aging in childhood. Both MAD and HGPS can be caused by mutations in the LMNA gene. In this stud...