# X-LINKED MENTAL RETARDATION--LINKAGE & CLINICAL STUDIES

> **NIH NIH R01** · UNIVERSITY OF MIAMI SCHOOL OF MEDICINE · 1994 · $302,317

## Abstract

X-linked mental retardation (XLMR) constitutes a major cause of mental
retardation in males.  Although significant progress has been made in the
last decade in understanding the Fragile X, little is known of the
remaining X-linked disorders which collectively cause 60-70% of XLMR.
Although 27 entities are documented in the present proposal, most families
with XLMR remain without a specific diagnosis.  Although suggestive X-
chromosomal localizations have been reported for a few of these disorders
in only one instance has the lod score reached significance.  In general,
direct laboratory diagnosis or prenatal diagnosis is not available for
these families.

The present investigation is designed to ascertain families with X-linked
mental retardation (excluding Fragile X families), and to map as many of
these disorders as possible using DNA probes and high resolution chromosome
studies.  This study will, therefore, contribute significantly to the
linkage map of the X chromosome.  Improved prenatal diagnosis for many of
these disorders will also be a likely outcome.  It is also designed to
determine whether certain of these clinical descriptions in fact, represent
the same disorder, and whether unusual genetic mechanisms are operative in
this group of families.  A combination of clinical, neuropsychological, MR
imaging, and other studies will be utilized to further define the clinical
and behavioral phenotypes of these disorders.  Overall, the study is
planned to ascertain and characterize 40-45 families in 5 years.

## Key facts

- **NIH application ID:** 2199868
- **Project number:** 5R01HD026202-05
- **Recipient organization:** UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
- **SAM.gov UEI:** F8THLJQSAF93
- **Principal Investigator:** HERBERT A LUBS
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1994
- **Award amount:** $302,317
- **Award type:** 5
- **Project period:** 1990-07-01 → 1996-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/2199868

## Citation

> US National Institutes of Health, RePORTER application 2199868, X-LINKED MENTAL RETARDATION--LINKAGE & CLINICAL STUDIES (5R01HD026202-05). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/2199868. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*