Phenotypes associated with this allele

• Allele Symbol: Lbr^ic
• Allele Name: ichthyosis
• Allele ID: MGI:1856063
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Lbr^ic/Lbr^ic	Not Specified	MGI:3603536
ht2	Lbr^ic/Lbr^+	Not Specified	MGI:3604081

Genotype
MGI:3603536

hm1

• Allelic Composition: Lbr^ic/Lbr^ic
• Genetic Background: Not Specified

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

mortality/aging

postnatal lethality ( J:13065 )

• incidence is correlated with degree mice are affected by deteriorating skin condition

behavior/neurological

decreased vocalization ( J:13065 )

• majority of mice are mute

reproductive system

cryptorchism ( J:13065 )

♂ • most males fail to develop a scrotum

constricted vagina orifice ( J:13065 )

♀ • severity of skin condition displaces vaginal opening over pubic symphysis

absent scrotum ( J:13065 )

• most males fail to develop a scrotum

reduced female fertility ( J:13065 )

♀

male infertility ( J:13065 )

♂ • cryptorchid males are invariable sterile

♂ • however, males with one or both testes descended are usually fertile

cellular

abnormal cell nucleus morphology ( J:5569 )

• chromatin in leucocytes and many other cells types is clumped

• cells of mutant mice contain about 10% more DNA than normal sibs

increased mitochondrial fission ( J:5740 )

• found in epidermis

endocrine/exocrine glands

cryptorchism ( J:13065 )

♂ • most males fail to develop a scrotum

respiratory system

abnormal respiration ( J:13065 )

growth/size/body

postnatal growth retardation ( J:13065 )

• mutant mice grow more slowly than normal sibs

integument

abnormal hair growth ( J:13065 )

• by the second week mice have a thin, short coat of curly hair instead of a full coat

• coats of older mice range from a thin, fuzzy coat to completely bare

• at 6 days there is only fluffy down on head and neck; dorsal guard hairs are scarsely visible

delayed hair appearance ( J:13065 )

abnormal vibrissa morphology ( J:13065 )

• whiskers of 2-day-old are shorter than normal

• at 3 days arrangement is irregular, some curved or criss-crossed

• whiskers are short and heavily curled by 2 weeks of age

short vibrissae ( J:13065 )

abnormal epidermal layer morphology ( J:5552 )

• dermal and epidermal recombination experiments indicate this locus acts in the epidermis

• dilated intercellular junctions found between the stratum spinosum and stratum granulosum are packed with membrane-coating and amorphous material

• contains excessively clumped tonofilaments and incresed numbers of mitochondria

abnormal epidermis stratum corneum morphology ( J:13065 )

• this layer was thickened

abnormal epidermis stratum granulosum morphology ( J:5740 )

• this layer is more prominent than in normal sibs

• ultrastructural analysis showed profuse keratin-forming structures, abnormally large keratohyaline granules, and persistent mitochondria

increased keratohyalin granule size ( J:5740 )

• abnormally large keratohyaline granules

epidermis stratum spinosum hyperplasia ( J:13065 )

scaly skin ( J:13065 )

abnormal skin condition ( J:13065 )

• individuals show variation in severity; in the most serious cases scales form rigid plates restricting movement and respiration

• during weeks 3 and 4, the skin dries, hardens, and is progressively sloughed in an anteriorposterior, dorsoventral pattern

limbs/digits/tail

tail necrosis ( J:13065 )

• tail may develop multiple constrictions with loss of tail tip through necrosis

Genotype
MGI:3604081

ht2

• Allelic Composition: Lbr^ic/Lbr⁺
• Genetic Background: Not Specified

cellular

abnormal cell nucleus morphology ( J:5569 )

• heterozygous mice have 5% more DNA than mutant sibs; 5% less DNA than +/+ sibs