A 2-year-old boy with psychomotor retardation, congenital unilateral ptosis, bilateral adducted thumbs, weakness of upper limbs, and Hirschsprung's disease (aganglionosis), with complete agenesis of the corpus callosum and hypoplasia of the inferior vermis and cerebellum is reported. His 24-year-old maternal uncle, with severe psychomotor retardation but none of the other physical problems, als...

Two families are described in which the Ehlers-Danlos syndrome is apparently transmitted as an X-linked recessive character. The results of tests for the Xg blood groups and for colour vision show that the locus for the Ehlers-Danlos syndrome is not close to that for the Xg groups nor very close to the locus for deutan colour-blindness.The clinical features of this variety of the Ehlers-Danlos ...

Three infant boys with bilateral absence of the kidneys and hypoplasia of the lungs are described. Two of the infants were brothers and the third was a first cousin. They were born to 2 sisters whose husbancs were unrelated to their wives and to each other. None of the parents had renal problems. The occurrence of this syndrome in 2 male sibs is suggestive of an autosomal recessive inheritance ...

INTRODUCTION Mendelian inheritance is based on the transmission of a single gene on a dominant, recessive or X-linked pattern. Discoveries on DNA structure, the genetic code, the genome and the observation that some characters and hereditary diseases do not follow classical mendelian inheritance have led researchers to define other patterns of transmission, referring particularly to multifactor...

Chronic granulomatous disease in males is familial and its transmission is is usually clearly x-linked. The mode of inheritance in females with the syndrome is unknown and the carrier state difficult to identify. Defective polymorphonuclear leukocyte bactericidal activity in this disease is associated with an absence of the respiratory burst generated in stimulated phagocytes and may be detecte...

X-linked diseases typically exhibit more severe phenotypes in males than females. In contrast, protocadherin 19 (PCDH19) mutations cause epilepsy in heterozygous females but spare hemizygous males. The cellular mechanism responsible for this unique pattern of X-linked inheritance is unknown. We show that PCDH19 contributes to adhesion specificity in a combinatorial manner such that mosaic expre...

The human X chromosome is the favorite chromosome of many geneticists because of its peculiar inheritance pattern and unique biology. The peculiar inheritance pattern stems from its hemizygosity in males and gives rise to a disproportionately high number of Mendelian diseases associated with a human chromosome. As high as 70% of the genes with a known function on the X are associated with disea...