Background: The oligophrenin 1 gene ("OPHN1") is an Rho-GTPase-activating protein involved in the regulation of the G-protein cycle required for dendritic spine morphogenesis. Mutations in this gene are implicated in X-linked mental retardation (XLMR). Methods: We report a deletion spanning exons 21 and 22 of the "OPHN1" gene identified by a…

In an attempt to improve the identification of the asymptomatic carrier of classic phenylketonuria (PKU) 59 male and female normal control Ss were differentiated from 18 males and females heterozgous for PKU. (DB)

Analysis of venous blood samples from 24 mothers of G1-trisomy-affected (Down's Syndrome) children and 23 mothers of chromosomally normal children indicated that mothers of G1-trisomy-affected children had a greater than expected involvement of the G-chromosomes in associations of acrocentric satellited (chromosome configuration) chromosomes.…

Discusses the Human Genome Project and the identification of Fragile X Syndrome, the most common inherited cause of mental retardation. Fragile X Syndrome is caused by an abnormal gene on the bottom of the X chromosome. Examined the phenotype of Fragile X Syndrome in males and females and the spectrum of learning difficulties caused by the…

Examined were eight patients with cerebro-hepato-renal syndrome of Zellweger (associated with severe cerebral dysfunction, hypotonia and unusual appearance). (CL)

Banding techniques were used in follow-up chromosome studies on two adult institutionalized retardates who had been previously described as having a low ridge count due to a high number of arches on the fingertips associated with undefined chromosomal abnormalities. (CL)

Post mortem examinations were done on two adult siblings (one female and one male) who had been clinically described as suffering from mental handicap, deaf mutism, ataxia, hypogonadism, and hormonal disorders. (DB)

EIGHTY-FIVE BOOKS AND ARTICLES DEALING WITH DOWN'S SYNDROME (MONGOLISM) ARE LISTED. DATING FROM 1933 THROUGH 1965, THE ITEMS CITED FOCUS ON BIOCHEMICAL AND GENETIC FACTORS AS WELL AS THE DEVELOPMENT OF THE MONGOLOID CHILD. (JD)

The paper reviews mental retardation research activities of the National Institute of Child Health and Human Development (NICHHD) and the National Institute of Neurological and Communicative Disorders and Stroke (NINCDS). Research activities are cited to illustrate the scope of NICHHD's efforts in a variety of biomedial areas. Activities are…

Resulting from a 1-day conference on mongolism, the book contains research studies and discussion summaries. Papers include "Parental Age, Live-Birth Order, and Pregnancy-Free Interval in Down's Syndrome in Japan" by E. Matsunaga, "Consanguineous Marriages and Mongolism" by H. Foressman and H. O. Akesson, "Correlation of Dermal Patterns on…

A case of partial trisomy of the short arms of chromosome number 11 resulting in profound retardation and multiple physical defects was confirmed by means of fluorescent karyotyping of the chromosomally balanced carrier father. (Author)