Phenotypes associated with this allele

• Allele Symbol: jb
• Allele Name: juvenile bare
• Allele ID: MGI:1856613
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	jb/jb	B6.Cg-jb/J	MGI:3799449
hm2	jb/jb	involves: C3HeB/FeJ * C57BL/6J	MGI:3799366

Genotype
MGI:3799449

hm1

• Allelic Composition: jb/jb
• Genetic Background: B6.Cg-jb/J

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

endocrine/exocrine glands

abnormal gland physiology ( J:39707 )

• Background Sensitivity: skin transplants from the C57BL/6J host background onto albino scid hosts do not show the hair loss indicating that the site of action of this mutation is not localized to the hair follicle but rather is systemic

integument

abnormal hair growth ( J:39707 )

• Background Sensitivity: at 14 to 15 days of age hair loss begins and progresses from rump forward, stopping by 20 to 21 days of age at a line on the head between the ears, after which the hair regrows from the head forward to the rump and males have an almost normal coat and females have a slightly sparce coat, which becomes more sparce with age

• Background Sensitivity: phenotypic expression is found on the C57BL/6J, ABP/Le, MEV/1Ty and C.B17-Prkdc backgrounds but has low expression on the C3HeB/FeJ, A/J, and CAST/Ei backgrounds and partial expression on the (B6 x C3HeB/FeJ) segregating background

abnormal hair cycle ( J:39707 )

• Background Sensitivity: at 19, 23, and 26 days of age hair follciles are severely distorted and the dermis becomes thickened, but by 26 days of age the skin begins to return to normal

Genotype
MGI:3799366

hm2

• Allelic Composition: jb/jb
• Genetic Background: involves: C3HeB/FeJ * C57BL/6J

craniofacial

abnormal incisor morphology ( J:14240 )

• breeding females, but not males or virgin females, are prone to incisor overgrowth and breakage, possibly due to poor mineralization

long incisors ( J:14240 )

growth/size/body

abnormal incisor morphology ( J:14240 )

• breeding females, but not males or virgin females, are prone to incisor overgrowth and breakage, possibly due to poor mineralization

long incisors ( J:14240 )

weight loss ( J:14240 )

• in some breeding females, likely associated with bad incisors

reproductive system

decreased litter size ( J:39707 )

behavior/neurological

ataxia ( J:14240 )

convulsive seizures ( J:39707 )

• convulsions are seen occasionally when the mutants are disturbed, such as when transfered between cages, and after these convulsions the mice are described as unusually nervous

nervous system

convulsive seizures ( J:39707 )

• convulsions are seen occasionally when the mutants are disturbed, such as when transfered between cages, and after these convulsions the mice are described as unusually nervous

integument

abnormal hair growth ( J:14240 , J:39707 )

• Background Sensitivity: at 14 to 15 days of age hair loss begins and progresses from rump forward, stopping by 20 to 21 days of age at a line on the head between the ears. After this the hair regrows from the head forward to the rump and males have an almost nomral coat and females have a slightly sparce coat, which becomes more sparse with age (J:39707)

premature hair loss ( J:14240 )

sparse hair ( J:39707 )

disheveled coat ( J:14240 )

• Background Sensitivity: in females after regrowth of the coat

abnormal hair shedding ( J:14240 , J:39707 )

skeleton

abnormal incisor morphology ( J:14240 )

• breeding females, but not males or virgin females, are prone to incisor overgrowth and breakage, possibly due to poor mineralization

long incisors ( J:14240 )