Oculocutaneous Albinism Type I or –Type 1A (OCA1A) is an autosomal

Autosome

An autosome is a chromosome that is not a sex chromosome, or allosome; that is to say, there is an equal number of copies of the chromosome in males and females. For example, in humans, there are 22 pairs of autosomes. In addition to autosomes, there are sex chromosomes, to be specific: X and Y...

 recessive skin disease associated with albinism

Albinism

Albinism is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes due to absence or defect of an enzyme involved in the production of melanin...

. This type of albinism is caused when the gene OCA1 does not function properly.

The location

Locus (genetics)

In the fields of genetics and genetic computation, a locus is the specific location of a gene or DNA sequence on a chromosome. A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map...

 of OCA1 may be written as "11q1.4-q2.1", meaning it is on the long arm of chromosome

Chromosome

A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...

 11

Chromosome 11 (human)

thumb|right|Chromosome 11 ChartChromosome 11 is one of the 23 pairs of chromosomes in humans. Humans normally have two copies of this chromosome. Chromosome 11 spans about 134.5 million base pairs and represents between 4 and 4.5 percent of the total DNA in cells...

, somewhere in the range of sub-band 4 of band 1, and sub-band 1 of band 2.