Five new subjects with ring chromosome 22.

Ring chromosome 22, a rare cytogenetic finding, was first described by Weleber et al. in 1968. Since then approximately 50 patients have been reported in the medical literature. We describe five previously unreported subjects with ring chromosome 22 syndrome, summarize the clinical findings of reported patients from the literature and discuss the involvement of the ring chromosome and clinical outcome. Our subjects demonstrated the prominent features of this syndrome including mental retardation, hypotonia, motor delay, lack of speech, full eyebrows, and large ears. In addition, two of our subjects had central nervous system malformations and regression. The lack of consistent physical abnormalities in our subjects further supports no consistent phenotype manifestations in this cytogenetic syndrome. The variable clinical manifestations seen in ring chromosome 22 subjects may be associated with loss of chromosome 22 sequences near the telomere or attributed to the genetic background of each subject. Similarly, recessive alleles unmasked by the deletion could also contribute to the phenotype.

Omphalocele in three generations with autosomal dominant transmission.

We report a family with nine subjects over three generations affected with an omphalocele requiring surgical intervention within the first few days of life. Because of the vertical transmission and male to male inheritance in our family, we conclude that an autosomal dominant gene caused the omphalocele in the affected family members. The paternal great grandfather of the proband was not clinically affected but produced two children with omphaloceles with different spouses.

Total anomalous pulmonary venous connection and a constellation of craniofacial, skeletal, and urogenital anomalies in a newborn and similar features in his 36-year-old father.

We report on a newborn male born to non-consanguineous parents with total anomalous pulmonary venous connection (TAPVC) and additional findings of malformed ears, hypertelorism, brachyphalangy in the hands, pterygium of the elbows, knees, and wrists, complex lower limb pre-axial polydactyly, tibial shortening, clubfeet, horseshoe kidney and a micropenis. He had a 46,XY karyotype. His 36-year-old father had similar craniofacial and limb anomalies suggesting an autosomal dominant syndrome with variable expression. Our patients may represent the 3rd and 4th examples of a newly-described syndrome by Baraitser et al. [(1997) Clin Dysmorphol 6:111-121] which is distinguished by malformed ears, complex pre-axial polydactyly and tibial aplasia in the lower limbs, severe brachyphalangy in the hands, and a micropenis.

Specific genetic diseases at risk for sedation/anesthesia complications.

UNLABELLED: We reviewed of a number of genetic diseases known or at risk for sedation or anesthesia complications. Some of these conditions are relatively common (e.g., Down's syndrome) whereas others are rare or present with multiple congenital anomalies that have an impact on health care delivery. We listed complications, recommended presedation evaluations, and included checklist items to assist the health care provider administering sedation and anesthesia. A better recognition and awareness of risk factors associated with specific genetic diseases should lessen the likelihood of complications during these procedures. IMPLICATIONS: This article provides a brief description of potential problematic genetic disorders and associated complications that may manifest during sedation or anesthesia. Recommendations for presedation evaluation and checklist items are given that may impact on the delivery of care for these patients.

Immunodeficiency in a patient with Baller-Gerold syndrome: a reason for early demise?

We describe the case of a 37-week-old, small-for-gestational-age, white baby girl born with Baller-Gerold syndrome (BGS), with craniosynostosis and partial absence of the corpus callosum, absent radius, and syndactyly. She died at 2 months of age because of overwhelming sepsis that appeared to be due to an underlying humoral immunodeficiency. Unexpected sudden death has been reported in patients with BGS, but there has been no previous documentation of immunodeficiency. We suggest that a basic immunologic and hematologic workup should be part of the standard of care of all patients affected with BGS or related syndromes.

Autosomal recessive form of connatal Pelizaeus-Merzbacher disease.

We report on a brother and sister with the connatal form of Pelizaeus-Merzbacher disease. This rare degenerative disease of white matter is reported to be transmitted as an X-linked recessive with an occasional affected female. Some authors have suggested that an autosomal recessive form exists. When this family is analyzed with other families in the literature, both X-linked and autosomal recessive inheritance must be considered.

Parental trisomy 21 mosaicism.

A family with three children with trisomy 21 in which the mother is a phenotypically normal, trisomy 21/normal mosaic was studied. Chromosome 21 fluorescent heteromorphisms were used to document that two of the three number 21's in two of the Down syndrome offspring were of maternal origin. Five cytogenetic surveys in which both parents of a child with trisomy 21 were studied have been reviewed. From these data, it is estimated that 3% of couples producing a child with trisomy 21 can be explained by parental mosaicism. From 17 informative sibships, with one parent mosaic, the segregation ratio was estimated to be 0.43 +/- 0.11.

Holoprosencephaly and endocrine dysgenesis in brothers.

We report 2 brothers with holoprosencephaly, endocrine dysgenesis, and micropenis. This combination has been reported once previously in sibs (2 sisters) by Hintz et al (1968). In that case, autosomal recessive inheritance may have been the cause. The same may be true in our patients, but X-linked recessive inheritance is not excluded.