Distribution of marker-Y chromosome containing cells in different tissues of a Turner mosaic patient with mixed gonadal dysgenesis.

We here describe a 12-year-old girl with numerous Turner stigmata and virilized external genitalia. Chromosome analysis of PHA stimulated lymphocytes using different banding techniques revealed a 45,X/46,X,+mar Turner mosaicism with the prominent marker present in about 90% of the blood cells. A PCR-based analysis using a set of 9 STS from different regions of the human Y chromosome indicated the presence of Y chromosomal material with a deletion breakpoint most likely within deletion interval 6. Because of the risk of gonadoblastoma for Turner patients carrying Y chromosomal material, and clinical indications of functional testicular tissue, a gonadectomy in addition to surgical correction of the external genitalia was performed. The histological analysis of the gonads showed a mixture of testicular tissue and ovarian stroma, thus indicating mixed gonadal dysgenesis. Fibroblasts from skin and different parts of the gonads were cytogenetically analyzed and showed a variable distribution of the Y-derived marker between 4% in skin, 11-31% in gonadal tissue and up to 90% in peripheral lymphocytes.

Hirschsprung disease: paternal transmission to a son.

Hirschsprung disease (HD) is genetically heterogeneous with approximately 4% familial occurrence. The recurrence risk is higher in patients with severe involvement. We describe the transmission of histotopochemically proven HD from a father with long aganglionic segment disease to a son with ultrashort segment disease. This observation suggests that the length of involvement in HD is related to the variable expression of the gene defect. It also suggests autosomal dominant inheritance of HD.

Sphingolipid activator protein 1 deficiency in metachromatic leucodystrophy with normal arylsulphatase A activity. A clinical, morphological, biochemical, and immunological study.

A 7-year-old boy had clinical features of metachromatic leucodystrophy (MLD), however, an increased urinary sulphatide excretion was found in the presence of normal arylsulphatase A (and alpha-galactosidase A) activity. A rectal biopsy showed metachromatically staining storage macrophages as well as nonmetachromatic, but PAS-positive, submucosal neurons filled with membranous cytoplasmic bodies. These two types of storage material led to testing for a sphingolipid activator protein (SAP) deficiency. Loading tests with sulphatide and globotriaosylceramide showed deficient turnover of both sphingolipids in cultured fibroblasts. Using the Ouchterlony method, there was no reactivity between a described anti-SAP 1 antiserum and the patient's fibroblast extracts. This new case of SAP-1 deficient MLD was compared with the four cases of this variant known from the literature. Our results indicate that rectal biopsy morphology and lipid loading biochemistry should prove useful for the screening of SAP defects.