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Microphthalmia, Syndromic 4

OMIM ID:

X-linked recessive

Microphthalmia, Syndromic 4

Alternate Names

MCOPS4
microphthalmia with ankyloblepharon and mental retardation

Defective Genes

?

Clinical Characteristics

Ocular Features

In several generations of an Irish family, 7 males with clinical anophthalmia were identified.  Ankyloblepharon was also present and X-rays of the orbits were identified.

Systemic Features

One patient was born with a cleft soft palate and had preauricular skin tags.  All individuals were considered to be mentally retarded with IQ’s less than 50.

Genetics

Inheritance

MCOPS4 is an X-linked condition based on a single reported family.  The responsible mutation has not been identified but a locus (Xq27-q28) likely to contain the gene has been identified by multipoint linage analysis.

Pedigree

X-linked recessive, carrier mother

X-linked disorders are caused by a mutation on the X chromosome and both sexes can pass this to their children.  If the mutation is in a recessive gene and carried by the mother, she usually does not have the disease since the normal X chromosome without the mutation neutralizes the mutation in the abnormal X chromosome.  However, half her sons will inherit the mutation-containing X chromosome and therefore have the X-linked disease.  Half the daughters will inherit the mutation-bearing X chromosome and are usuallly healthy 'carriers'.

Image
Sample pedigree of X-linked recessive inheritance, carrier mother

X-linked disorders are caused by a mutation on the X chromosome and both sexes can pass this to their children. If the mutation is in a recessive gene and carried by the mother, she usually does not have the disease since the normal X chromosome without the mutation neutralizes the mutation in the abnormal X chromosome. However, half her sons will inherit the mutation-containing X chromosome and therefore have the X-linked disease. Half the daughters will inherit the mutation-bearing X chromosome and are usuallly healthy 'carriers'.

X-linked recessive, father affected

X-linked disorders are caused by a mutation on the X chromosome and both sexes can pass this to their children.  If the mutation is in a recessive gene and carried by the father, he has the disease since his only X chromosome is mutant and he has no normal X to blunt the effects of the abnormal gene.  His sons only receive his Y chromosome and thus are all normal.  However, all his daughters receive his one and only X chromosome and will be healthy 'carriers'.  Thus such males will have no affected children but half their grandsons from those daughters will have the same disease as he does.

Image
Sample pedigree of X-linked recessive inheritance, father affected

X-linked disorders are caused by a mutation on the X chromosome and both sexes can pass this to their children. If the mutation is in a recessive gene and carried by the father, he has the disease since his only X chromosome is mutant and he has no normal X to blunt the effects of the abnormal gene. His sons only receive his Y chromosome and thus are all normal. However, all his daughters receive his one and only X chromosome and will be healthy 'carriers'. Thus such males will have no affected children but half their grandsons from those daughters will have the same disease as he does.

Treatment & Management

No treatment is known.

Publications

Displaying 1 - 1 of 1

X-linked clinical anophthalmos Localization of the gene to Xq27-Xq28

PubMedID: 1679229