Apparent Smith‐Lemli‐Opitz syndrome and Miller‐Dieker syndrome in a family with segregating translocation t(7;17)(q34;p13.1)

Abstract

We describe a family in which one male infant presented with Miller-Dieker syndrome and four male relatives had a phenotype similar to the Smith-Lemli-Opitz (SLO) syndrome. High resolution cytogenetic analysis on the child with Miller-Dieker syndrome showed 46,XY,-17,+der17t(7;17)(q34:p13.1). Paternal chromosomes showed a balanced translocation: 46,XY,t(7;17)(q34:p13.1). The paternal grandmother had a history of multiple miscarriages, and a paternal uncle had two sons who died neonatally. Chromosomes on these children and their father had originally been reported as normal. There was also a paternal cousin to the father of the propositus who had had two sons with similar clinical findings. A diagnosis of SLO syndrome was considered. Image enhancement techniques on previous suboptimal preparations on these four children documented the subtle unbalanced translocation 46,XY,-7,+der7t(7;17)(q34:p13.1). Subsequent high resolution analysis on one of these four children who was still living confirmed this chromosome constitution. It is postulated that these apparent SLO cases may represent a contiguous gene syndrome in which SLO or a separate entity closely mimicking the syndrome in included.

Molecular cloning and expression of the human Δ7-sterol reductase

“…A 263-bp sequence-tagged sequence (WI-16597), identical with the human ⌬7-sterol reductase cDNA sequence, was assigned to human chromosome 11 between D11S913 and D11S1337 (27). Some patients with the SLO syndrome carry a translocation on chromosome 7q, but no well documented families are known (28)(29)(30). The cDNA for the ⌬7-sterol reductase therefore will be important to clone the ⌬7-sterol reductase gene and to identify additional proteins possibly required for the conversion of 7-dehydrocholesterol.…”

Lipid metabolism in myelinating glial cells: lessons from human inherited disorders and mouse models

“…Scale bar, 0.5 m. Sciatic nerve isolation and electron microscopy were done as described in ( 110 ). CNS defects in white matter are common, often involving corpus callosum absence or hypoplasia (36)(37)(38)(39)(40)(41)(42), and reported to involve absence of myelin ( 42 ) and demyelination ( 43 ), but detailed analysis of myelin structure has not yet been described. The relative contribution of either cholesterol depletion or 7-dehydro-cholesterol and 8-dehydro-cholesterol accumulation in white matter abnormalities is currently unclear.…”

Risk of abnormal pregnancy outcome in carriers of balanced reciprocal translocations involving the Miller-Dieker syndrome (MDS) critical region in chromosome 17p13.3

“…A review of the literature yielded five additional translocation families, four of which were ascertained through an index case with MDS [Alvarado et al, 1993;Berry et al, 1989;Masuno et al, 1995;Van ZelderenBhola et al, 1997]. The other was ascertained via an index case with dup(17p) and a less severe phenotype [Köhler et al, 1994].…”

“…Another woman from family F14 and several of her descendants may have been carriers; she had a son and three great-grandchildren who died in infancy. Again, clinical information was limited, so these individuals were not counted in the analysis [Berry et al, 1989].…”